Plant Resources of South-East Asia

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Plant Resources ofSouth-East Asia Noll Auxiliary plants I. Faridah Hanum and L.J.G. van der Maesen (Editors)

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Backhuys Publishers, Leiden 1997

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D R I. FARIDAH HANUM received her

first degree in Botany from 'Universiti Kebangsaan Malaysia', Bangi, Selangor in 1984, and her PhD from the University of Reading for a thesis on the Systematic Studies on the South-East Asian Ormosia. On returning to Malaysia, she pursued her career as a lecturer in dendrology and forest botany at the Faculty of Forestry, 'Universiti Pertanian Malaysia', Serdang. She is presently also involved in the Tree Flora of Sabah and Sarawak and is actively doing research on the plant diversity of the hill forests of Malaysia. PROFESSOR L.J.G. VAN DER MAESEN is a tropical agronomist-botanist who graduated from Wageningen Agricultural University in 1968. His doctoral thesis, defended in 1972, was a monograph on Cicer. He has worked in Iraq for FAO and from 1974 to 1984 was a principal germplasm botanist with ICRISAT, India. In 1984, he joined the Department of Plant Taxonomy at Wageningen Agricultural University as professor and head of department. His publications cover various aspects ofplant genetic resources (notably of pulses) and their taxonomy, collection, conservation and use. He has made several collection trips to Asia and Africa. In 1989, he was one of the editors of Prosea No 1. Pulses.

w^.vvuNîvEBsrrar ISBN 90-73348-66-8 NUGI 835 Design: Frits Stoepman bNO. © Prosea Foundation, Bogor, Indonesia, 1997.

No part of this publication, apart from bibliographic data and brief quotations embodied in critical reviews, may be reproduced, re-recorded or published in any form including print, photocopy, microfilm, electric or electromagnetic record without written permission from the copyright holder, Prosea Foundation, c/o Publication Office, P.O. Box 341, 6700 AH Wageningen, the Netherlands. Printed in the Netherlands. Published and distributed for the Prosea Foundation by Backhuys Publishers, P.O. Box 321,2300 AH Leiden, the Netherlands.

Contents

Editors and contributors 8 Prosea Board ofTrustees and Personnel 13 Foreword 16 1 Introduction 19 1.1 Definition ofauxiliary plants 19 1.2 Role ofauxiliary plants in agriculture and forestry 20 1.2.1 Major groups and uses 20 1.2.2 Importance 31 1.2.3 Selection of species 32 1.3 Botany 32 1.3.1 Taxonomy 32 1.3.2 Growth and development 32 1.3.3 Atmospheric nitrogen fixation and mycorrhizae 33 1.4 Ecology 36 1.4.1 Ecological interactions 36 1.4.2 Aspeetsyof.soil,fertility 39 1.5 Management42, 1.5.1 Planting material 42 1.5.2 Establishment 43 1.5.3 Post-establishment practices 43 1.6 Genetic resources and breeding 44 1.7 Prospects 45 2 Alphabetical treatment ofspecies 47 Acacia aulacocarpa Acacia auriculiformis Acacia crassicarpa Acacia glauca Aeschynomene afraspera Albizia chinensis Albizia procera Alnus Azadirachta indica Bruguiera cylindrica Bruguiera sexangula

: brown salwood 49 :northern black wattle 52 :northern wattle 56 :wild dividivi 58 :sola pith 60 :silk tree 63 : white siris 65 :alder 68 : neem 71 :black mangrove 76 :black mangrove 78

Calliandra calothyrsus Calopogonium mucunoides Casuarina equisetifolia Casuarina junghuhniana Centrosema pubescens Chromolaena odorata Cordia alliodora Crotalaria micans Crotalaria pallida Crotalaria spectabilis Crotalaria trichotoma Cyamopsis tetragonoloba Dactyladenia barteri Derris microphylla Desmodium adscendens Eichhornia crassipes Erythrina fusca Erythrina poeppigiana Erythrina subumbrans Erythrina variegata Eucalyptus camaldulensis Eucalyptus tereticornis Eucalyptus urophylla Flemingia macrophylla Gliricidia sepium Grevillea robusta Homonoia riparia Indigofera hendecaphylla Indigofera hirsuta Indigofera suffruticosa Ipomoea Kleinhovia hospita Kummerowia Lespedeza cuneata Leucaena diversifolia Leucaena leucocephala Lupinus Maesopsis eminii Melia azedarach Melilotus Mikania Mimosa diplotricha Mucuna pruriens cv. group Utilis Paraserianthes falcataria Peltophorum dasyrhachis Pongamia pinnata Prosopis juli flora Psophocarpus scandens

calliandra 79 calopo 84 coast she-oak 86 red-tipped ru 89 centro 92 Siam weed 95 cordia 98 Caracas rattlebox 101 smooth rattlebox 103 showy rattlebox 105 curare pea 107 guar 109 monkey fruit 113 vetch tree 115 tick clover 117 water hyacinth 118 purple coral-tree 121 mountain immortelle 123 December tree 127 Indian coral tree 130 river red gum 132 forest red gum 137 Timor white gum 140 apa-apa 144 gliricidia 147 silky oak 151 water-willow 155 creeping indigo 156 hairy indigo 159 anil indigo 161 ipomoea 163 guest tree 166 kummerowia 167 Chinese lespedeza 170 leucaena 173 leucaena 175 lupin 180 umbrella tree 184 Chinaberry 187 sweetclover 191 mikania 194 giant sensitive plant 196 velvet bean 199 paraserianthes 203 peltophorum 207 pongam 209 mesquite 211 psophocarpus 214

Pueraria phaseoloides Rhizophora apiculata Samanea saman Schleichera oleosa Senna didymobotrya Senna hirsuta Senna siamea Sesbania Sesbania rostrata Sonneratia ovata Tephrosia Candida Tephrosia purpurea Tephrosia vogelii Thespesia populnea Trema orientalis Vigna hosei Vigna marina Vigna trilobata Vigna vexillata

tropical kudzu 217 bakau minyak 220 rain tree 224 Macassar oiltree 227 candelabra tree 229 woolly wild sensitive plant 231 Siamese senna 232 sesbania 236 sesbania 240 sonneratia 242 white tephrosia 244 purple tephrosia 246 Vogel's tephrosia 248 Pacific rosewood 251 charcoal tree 252 Sarawak bean 255 dune bean 257 phillipesara 259 wild mung bean 261

3 Minor auxiliary plants 264 4 Auxiliary plants with other primary use 308 Literature 322 Acknowledgments 331 Acronyms oforganizations 332 Glossary 334 Sources ofillustrations 350 Index of scientific plant names 357 Index ofvernacular plant names 375 The Prosea Foundation 385

Editors and contributors

General editors of the Prosea Handbook P.C.M. Jansen, E. Westphal and N. Wulijarni-Soetjipto Editorial staff of this volume Editors: I. Faridah Hanum and L.J.G. van der Maesen - Associate editors: B.T. Kang, L.P.A. Oyen, R.J. van den Beldt, M. Wessel, E. Westphal (agronomic aspects) and P.C.M. Jansen (botanical aspects) - Illustrator: P. Verheij-Hayes - Language corrector: J. Burrough-Boenisch

Contributors - N.O. Aguilar, Institute of Biological Sciences, College of Arts and Sciences, University ofthe Philippines at Los Banos, College, Laguna 4031,the Philippines (Crotalaria pallida, Tephrosia purpurea, Vigna marina) - S. Ahmed, Agventures Inc., 781 Eleele Place, Honolulu, HI 96825, Hawaii, United States (Azadirachta indica, Melia azedarach) - R. Akkasaeng, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand (Albizia chinensis, Samanea saman) - A. Aminah, MARDI, P.O. Box 12301, 50774 Kuala Lumpur, Malaysia (Calopogonium mucunoides) - R.K. Arora, IPGRI Office for South Asia, c/o NBPGR, Pusa Campus, New Delhi 110 012, India (Melilotus) N.T. Baguinon, Forest Biological Science Department, College of Forestry, University ofthe Philippines at Los Banos, College, Laguna 4031,the Philippines (Erythrina fusca) - M. Becker, Soil Microbiology Division, IRRI, P.O. Box 933, Manila, the Philippines (Aeschynomene afraspera) - E. Boer, Prosea Publication Office, Department of Plant Taxonomy, Wageningen Agricultural University, P.O. Box 341, 6700 AH Wageningen, the Netherlands {Eucalyptus tereticornis, Minor auxiliary plants: Acacia oraria, Casuarina cunninghamiana, Casuarina glauca, Casuarina oligodon, Gymnostoma rumphianum, Gymnostoma sumatranum, Paraserianthes lophantha, Salix tetrasperma) - T. Boonkerd, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand (Bruguiera cylindrica, Bruguiera sexangula)

EDITORS AND CONTRIBUTORS

J.L. Brewbaker, Department of Horticulture, University of Hawaii, 3190 Maile Way, Honolulu, HI 96822-2279, Hawaii, United States (Leucaena leucocephala) A. Budelman, Royal Tropical Institute, Mauritskade 63, 1092 AD Amsterdam, the Netherlands (Flemingia macrophylla) H.T. Chan, Environmental Science Division, FRIM, P.O. Box 201, Kepong, 52109 Kuala Lumpur, Malaysia (Bruguiera cylindrica, Bruguiera sexangula, Rhizophora apiculata) Chen Chin Peng, Livestock Research Centre, MARDI, P.O. Box 12301, 50774 Kuala Lumpur, Malaysia (Calopogonium mucunoides, Centrosema pubescens) S. Danimihardja, Prosea Network Office, Herbarium Bogoriense, P.O. Box 234, Bogor 16122, Indonesia (Acacia glauca) T. Djarwaningsih, Herbarium Bogoriense, Jl. Juanda 22, Bogor 16122, Indonesia {Indigofera hirsuta) J.C. Doran, Division of Forestry, CSIRO, P.O. Box E 4008, Kingston, ACT 2604, Canberra, Australia {Eucalyptus camaldulensis, Eucalyptus urophylla) C. Doungsa-ard, Kasetsart University, Bangkhen, Bangkok 10900, Thailand {Mimosa diplotricha) P.K. Eng, MARDI, P.O. Box 12301, 50774 Kuala Lumpur, Malaysia (Desmodium adscendens) I. Faridah Hanum, Department of Forest Production, Faculty of Forestry, Agricultural University Malaysia, 43400 UPM, Serdang, Selangor, Malaysia (Thespesia populnea, Trema orientalis) M. Fuentes, Departamento de Ciencias y Recursos Agricolas y Forestales, Universidad de Córdoba, P.O. Box 3048, Cordoba, Spain (Lupinus) R.C. Gutteridge, Department of Agriculture, The University of Queensland, St Lucia 4072, Queensland, Australia (Albizia chinensis, Senna siamea) R.A. Halim, Department of Agronomy & Horticulture, Agricultural University Malaysia, 43400 UPM, Serdang, Selangor, Malaysia (Pueraria phaseoloides) C E . Harwood, CSIRO Forestry and Forest Products, P.O. Box E4008, Kingston, ACT 2604, Australia (Acacia crassicarpa, Grevillea robusta) D. Hou, Rijksherbarium/Hortus Botanicus, P.O. Box 9514, 2300 RA Leiden, the Netherlands (Rhizophora apiculata) LB. Ipor, Faculty of Resource Science & Technology, University of Malaysia, Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia (Leucaena diversifolia, Mikania, Sesbania, Sesbania rostrata) S. Iwasa, Tropical Agricultural Research Center (TARC), 1-2 Ohwashi, Tsukuba, Ibaraki 305, Japan (Schleichera oleosa, Minor auxiliary plants: Inocarpus fagifer) R.J. Jones, CSIRO Tropical Agriculture, Private Mail Bag, Aitkenvale, Queensland 4814, Australia (Leucaena leucocephala) J. Jukema, P.O. Box4280, Curaçao, Netherlands Antilles (Acacia glauca) Kamis Awang, Graduate School Universiti Pertanian Malaysia, 43400 UPM, Serdang, Selangor, Malaysia (Acacia auriculiformis) B.T. Kang, Department of Crops and Soil Sciences, University of Georgia, Athens GA 30602, United States (Dactyladenia barteri) D.O. Ladipo, CENRAD, P.M.B. 5052, Ibadan, Nigeria (Dactyladenia barteri)

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AUXILIARY PLANTS

- A. Latiff, Department of Botany, Faculty of Life Sciences, National University of Malaysia, 43600 Bangi, Selangor, Malaysia (Kleinhovia hospita, Maesopsis eminii, Thespesia populnea) - L. López-Bellido, Departamento de Ciencias y Recursos Agrfcolas y Forestales, Universidad de Córdoba, P.O. Box 3048, Cordoba, Spain (Lupinus) - R.F. Maligalig, Prosea Country Office Philippines, PCARRD, P.O. Box 425, Los Banos, Laguna 4030, the Philippines (Mucuna pruriens cv. group Utilis) - P.N. Mathur, IPGRI Office for South Asia, c/o NBPGR, Pusa Campus, New Delhi 110 012, India (Melilotus) - S.J. Midgley, Tree Improvement and Genetic Resources, CSIRO Forestry and Forest Products, P.O. Box 4008, Kingston, ACT 2604, Australia (Casuarina equisetifolia) - J.A. Mosjidis, Department of Agronomy and Soils, College of Agriculture, Auburn University, 202 Funchess Hall, Alabama 36849-5412, United States (Kummerowia, Lespedeza cuneata) - B. Na-songkhla, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand (Erythrina variegata) - P.E. Neil, 11 Grenada Drive, Whitley Bay, Tyne & Wear NE26 IHR, United Kingdom {Alnus, Cordia alliodora) - Nguyen Nghia Thin, Department of Botany, University of Hanoi, 90 Nguyen Trai Str., Dong Ha, Hanoi, Vietnam (Homonoia riparia) - I.M. Nitis, Department of Nutrition and Tropical Forage Science, Udayana University, Jalan Jenderal Sudirman, Denpasar, Bali, Indonesia (Gliricidia septum) - C. Niyomdham, The Forest Herbarium, Royal Forest Department, 61 Phahonyothin Road, Bangkhen, Bangkok 10903,Thailand (Crotalaria micans, Crotalaria spectabilis) - H.C. Ong, Department of Botany, University of Malaya, 59100 Kuala Lumpur, Malaysia (Minor auxiliary plants:Ageratina riparia) - B. Othman, Faculty of Resource Science & Technology, University of Malaysia, Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia (Sonneratia ovata) - L.P.A. Oyen, Prosea Publication Office, Department of Agronomy, Wageningen Agricultural University, P.O. Box 341, 6700 AH Wageningen, the Netherlands (Crotalaria trichotoma, Erythrina poeppigiana, Ipomoea, Pongamia pinnata, Prosopis juliflora, Sesbania, Tephrosia Candida) - C. Parmar, 192/4 Jail Road, Mandi, H.P. 175001, India (Cyamopsis tetragonoloba) - A.H. Pieterse, Department ofAgriculture and Enterprise Development, Royal Tropical Institute, Mauritskade 63, 1092 AD Amsterdam, the Netherlands (Eichhornia crassipes) - K. Pinyopusarerk, Australian Tree Seed Centre, CSIRO Forestry and Forest Products, P.O. Box E4008, Kingston, ACT 2604, Australia (Acacia aulacocarpa, Acacia crassicarpa, Casuarina junghuhniana) - R. Prasad, State Forest Research Institute, Jabalpur, Madhya Pradesh, India (Minor auxiliary plants: Grevillea banksii, Grevillea pteridifolia) - I.K. Rika, Department of Extension Services, Udayana University, Jalan Jenderal Sudirman, Denpasar, Bali, Indonesia (Calliandra calothyrsus)

EDITORS AND CONTRIBUTORS

J.P. Rojo, Forest Products Research & Development Institute (FPRDI), College, Laguna 4031,the Philippines (Paraserianthes falcataria) Rudjiman, Faculty of Forestry, Gadjah Mada University, Bulaksumur, Yogyakarta, Indonesia (Peltophorum dasyrhachis) Rugayah, Herbarium Bogoriense, Jl. J u a n d a 22, Bogor 16122, Indonesia (Derris microphylla) R.O. Russo, School of Forestry & Environmental Studies, Yale University, 370 Prospect Street, New Haven, CT 06511, United States {Erythrina fusca) Salma Idris, MARDI, P.O. Box 12301, 50774 Kuala Lumpur, Malaysia (Azadirachta indica, Melia azedarach) H. Sangat-Roemantyo, Herbarium Bogoriense, Jl. Juanda 22, Bogor 16122, Indonesia {Senna hirsuta) H.G. Schabel, Department ofForestry, College ofNatural Resources, University ofWisconsin, Stevens point, WI 54481, United States (Maesopsis eminii) M.E. Siregar, Balai Penelitian Ternak, Ciawi, P.O. Box 123800, Bogor, Indonesia (Flemingia macrophylla) J.J.P. Slaats, Lindelaan 54, 6711 MV Ede, the Netherlands (Chromolaena odorata) C.T. Sorensson, New Zealand Forest Research Institute, Division of Biotechnology, Genetics and Tree Improvement Unit, Private Bag 3020, Rotorua, New Zealand (Leucaena leucocephala) M.S.M. Sosef, Prosea Publication Office, Department of Plant Taxonomy, Wageningen Agricultural University, P.O. Box 341, 6700 AH Wageningen, the Netherlands (Minor auxiliary plants) B. Sunarno, Herbarium Bogoriense, Jl. Juanda 22, Bogor 16122, Indonesia (Indigofera hendecaphylla, Indigo fera suffruticosa, Ipomoea, Senna didymobotrya, Tephrosia vogelii) H. Sutarno, Prosea Country Office Indonesia, Herbarium Bogoriense, P.O. Box 234, Bogor 16122, Indonesia (Mikania) R. Sylvester, c/o Prosea Country Office Malaysia, FRIM, Jalan FRIM, Kepong, Karung Berkunci 201, 52109 Kuala Lumpur, Malaysia (Casuarina equisetifolia) C S . Tawan, Faculty of Resource Science & Technology, University of Malaysia, Sarawak, 94300 Kota Samarahan, Sarawak, Malaysia (Mimosa diplotricha) J.K. Teitzel, Wairuna Cattle Co Pty Ltd, Wairuna Station, Mount Garnet, Queensland 4872,Australia (Centrosema pubescens) W. Thephuttee, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand (Minor auxiliary plants: Uraria crinita, Uraria lagopodioides) K. Thothathri, Botany Field Research Laboratory, Madras University, Maduravoyal, Madras-602 102, India (Derris microphylla) L. Tipot, 163B, Lot 463,Lorong 4A2, Tabuan Laru, 93350 Kuching, Sarawak, Malaysia (Minor auxiliary plants:Andira inermis) J.W. Turnbull, P.O. Box 1571, Canberra, ACT 2601,Australia (Acacia auriculiformis, Eucalyptus urophylla) Umi Kalsom Yusuf, Department of Biology, Faculty of Science, Agricultural University Malaysia, 43400 UPM, Serdang, Selangor, Malaysia (Erythrina subumbrans)

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- R.J. van den Beldt, 5/1637 Soi 13, Ban Prachachuen, Samakee Road, Pakkret, Nonthaburi 11120, Thailand - L.J.G. van der Maesen, Department of Plant Taxonomy, Wageningen Agricultural University, Generaal Foulkesweg 37, 6703 BL Wageningen, the Netherlands (Prosopis juliflora, Introduction, Minor auxiliary plants) - A.C.J, van Leeuwen, p/a Koeriersdienst BZ (Nicaragua, P.O. Box 20062), 2500 EB Den Haag, the Netherlands (Cordia alliodora) - M. van Noordwijk, ICRAF-South-East Asia, P.O.Box 161, Bogor 16001, Indonesia (Peltophorum dasyrhachis) - J.L.C.H. van Valkenburg, Prosea Publication Office, Department of Plant Taxonomy, Wageningen Agricultural University, P.O. Box 341,6700 AH Wageningen, the Netherlands (Albizia procera) - M. Wessel, Department of Forestry, Wageningen Agricultural University, P.O. Box 342, 6700 AH Wageningen, the Netherlands (Introduction) - K.F. Wiersum, Department of Forestry, Wageningen Agricultural University, P.O. Box 342, 6700 AH Wageningen, the Netherlands (Calliandra calothyrsus, Gliricidia sepium) - C.C. Wong, MARDI, P.O. Box 12301, 50774 Kuala Lumpur, Malaysia (Desmodium adscendens) - K.C. Wong, Department of Agronomy and Horticulture, Faculty of Agriculture, Agricultural University Malaysia, 43400 UPM, Serdang, Selangor, Malaysia (Vigna hosei, Vigna trilobata, Vigna vexillata) - L.J. Wong, MARDI, P.O. Box 186, Pejabat Besar Pos 41720, Kelang, Selangor, Malaysia (Cyamopsis tetragonoloba) - W. Wongkaew, Department of Botany, Faculty of Science, Kasetsart University, Bangkhen, Bangkok 10903,Thailand {Eucalyptus camaldulensis) - N. Wulijarni-Soetjipto, Prosea Network Office, Herbarium Bogoriense, P.O. Box 234, Bogor 16122, Indonesia (Mucuna pruriens cv. group Utilis, Psophocarpus scandens)

Prosea Board ofTrustees and Personnel

(February 1997) Board of Trustees Aprilani Soegiarto (LIPI, Indonesia), chairman C.M. Karssen (WAU, the Netherlands), vice-chairman Abdul Razak Mohd. Ali (FRIM, Malaysia) Misty Baloiloi (UNITECH, Papua New Guinea) B.P. del Rosario (PCARRD, the Philippines) Chalermchai Honark (TISTR, Thailand) Dang Huy Huynh (IEBR, Vietnam) J.M. Schippers (PUDOC-DLO) Soekiman Atmosoedarjo (à titre personnel) Sampurno Kadarsan (à titre personnel) Personnel Indonesia Soetikno Wirjoatmodjo, Programme Leader Hadi Sutarno, Country Officer Hernowo, Assistant Country Officer S. Rochani, Assistant Country Officer Z. Chairani, Assistant Country Officer Malaysia Abdul Razak Mohd. Ali, Programme Leader Elizabeth Philip, Country Officer Mohd. Rizal bin Mohd. Kassim, Assistant Country Officer Papua New Guinea P. Siaguru, Programme Leader R. Matu, Country Officer T. Brookings, Assistant Country Officer

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The Philippines B.P. del Rosario, Programme Leader R.F. Maligalig, Country Officer V.C. Fandialan, Assistant Country Officer N.P. Gesmundo, Assistant Country Officer G.P. Lantacon, Assistant Country Officer Thailand Soonthorn Duriyaprapan, Programme Leader Taksin Artchawakom, Country Officer Vietnam Nguyen Tien Ban, Programme Leader Dzuong Due Huyen, Country Officer La Dinh Moi,Assistant Country Officer Nguyen Van Dzu, Assistant Country Officer Network Office, Bogor, Indonesia J. Kartasubrata, Head Darlina, Secretary I.Afandi, Distribution Officer S. Brotonegoro, Scientific Officer S. Danimihardja, Regional Data Bank Officer S.S. Harjadi, Extension Officer F. Indi, Production Assistant A. Rahmat Hadi, Documentation Assistant A. Suharno, Financial Officer W. Wiharti, Documentation Assistant N. Wulijarni-Soetjipto, General Editor Jajang bin Musli, Office Assistant Publication Office, Wageningen, the Netherlands J.S. Siemonsma, Head E.M. Fokkema-Lentink, Secretary E. Boer, Forestry Officer M. Brink, Agronomy Officer H.C.D. de Wit, Scientific Adviser J.M. Fundter, Forestry Officer J.W. Hildebrand, Forestry Officer P.C.M. Jansen, General Editor R.H.M.J. Lemmens, Plant Taxonomy Officer L.P.A. Oyen, Documentation Officer M.S.M. Sosef, Plant Taxonomy Officer

EDITORS AND CONTRIBUTORS

E. Westphal, General Editor W.P.M. Wolters, Programme Secretary

15

Foreword

This volume in the Prosea handbook series is dedicated to auxiliary plants in agriculture and forestry. Any plant that forms part of a land-use system and provides a service and/or a product that is secondary to the main outputs of that system can be classified as an auxiliary plant. One of the major service functions of this group of plants in agriculture and forestry, including agroforestry, is the maintenance and improvement of soil fertility such as by mulching, shading, shelter, green manuring and cover crops for erosion control. Production roles, on the other hand, may include fuelwood, domestic timber, forage, food, fibres, staking and support material. In many farmers' practices the cultivation of herbaceous crops is combined with trees. In these land-use systems, trees or shrubs are grown in association with agricultural crops or pastures in a spatial arrangement or a rotation, in which both ecological and economic interactions exist between the trees and other components of the system. Appropriate agroforestry systems can control erosion, maintain soil organic matter and physical properties, and promote efficient nutrient cycling. At the beginning ofthis century the use of auxiliary plants in South and SouthEast Asia was mainly restricted to plantation agriculture. Since then, however, interest in the service and/or production roles of auxiliary plants has intensified significantly over the last decades resulting in the establishment of international research centres in this field of science. From this volume of the Prosea handbook it appears t h a t a fairly large number of auxiliary plants is not yet commonly used in South-East Asia on a large scale, but their performance outside the region is well-known and initial trials in South-East Asia have shown promise. In this sense this publication is not only a witness of well-used, or earlier-used and since then forgotten plants, but also of future promising ones. This publication also shows t h a t there is a great discrepancy in data available. The amount of interest, research efforts, hence output of data, vary considerably. Some plants are little studied and are merely condoned to grow as weeds to be ploughed in for the purpose of green manure. Others play a more prominent role and have been researched in more detail. The information presented here is very much the result of a collective effort of an international group of scientists. It is gratifying that the approach of Prosea could muster so much cooperation. The Board and personnel of the Prosea Foundation are to be congratulated on this excellent comprehensive overview of auxiliary plants. Finally, I sincerely hope that this book will be instrumental in focusing attention to the important issue of how to combine agriculture and forestry in order to raise the production of food, forage, fibre, fuel and timber, and how

FOREWORD

to improve income and living standards for the rural population of SouthEast Asia. Nairobi, February 1997 Dr. Pedro A. Sanchez Director General International Centre for Research in Agroforestry (ICRAF)

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1 Introduction

1.1 Definition of auxiliary plants Any plant that forms part of a land-use system and provides a service and/or a product that is secondary to the main outputs of a system, can be classified as an auxiliary plant. The plants covered in this volume are an odd array; what they have in common is their role in agriculture and forestry. Auxiliary plants do not deliver primary products, but assist the farmer or forester to better produce such products. They have a service role. In the terminology ofthe International Centre for Research in Agroforestry (ICRAF) 'service functions' are the production of mulch, shade, shelter, atmospheric nitrogen fixation and erosion control, whereas 'production functions' include supply of firewood, stakes, fruits, vegetables and fodder. Fuelwoods as a primary product are included here, since many fuelwoods are planted on farmland and often have a service function as well. They are the main source of energy for many households. On the other hand, the poles produced for building and fencing, such as from Gmelina arborea Roxb., are covered in the volume on Timber Trees, as timber also covers non-sawn wood. Plants with other primary uses may also have a secondary role as auxiliary crop. However, all the species dealt with in this volume (except fuelwood) have a primary role as a service crop. Multiple uses and dual roles are often difficult to separate quantitatively, and the decision to assign a particular species to a particular commodity group is sometimes arbitrary ('t Mannetje & Jones, 1992). The commodity subgroupings made for the auxiliary plants are: shade and nurse trees, cover crops, green manures, mulches, fallow crops, live fences, wind-breaks and shelter-belts, erosion-controlling plants, land reclamation species, live supports and stakes, and fuelwood (both firewood and the woody species used for charcoal). Of course, many timber species have a secondary use as fuel. Also, many cover crops are good forage. It should be noted that some plants important as water-clearing agents are also dealt with in this volume. Furthermore, in certain production systems a species may have an auxiliary function, whereas in another it may supply primary products. Sometimes, both functions are combined, e.g. grazed cover crops in coconut plantations. Moreover, some important auxiliary plants are also among the most important forages; therefore, a few of the species dealt with in the volume on Forages are highlighted as well. An early standard reference work on auxiliary plants in South-East Asia was published in the late 1940s (Ossewaarde «St Wellensiek, 1946).

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AUXILIARY PLANTS

1.2 Role of auxiliary plants in agriculture and forestry 1.2.1 Major groups and uses Auxiliary plants can be grouped in several ways. How the species concerned is used provides a practical way of subdivision. Auxiliary plants may also be grouped according to their habit: plants in all major habit groups - erect herbs, herbaceous and woody creepers, or climbers, shrubs and trees - may play a service role. The plant's habit is clearly of prime importance for certain service roles. Not all groups are mutually exclusive, and some plants play many roles. Table 1gives an indication of the various functions of auxiliary plants. The 12 auxiliary functions discerned are described below. Shade and nurse trees Shade trees are primarily used to manipulate the levels ofincoming light to the light requirements of associated crops such as cocoa, coffee or lowland tea. The shade requirements of these perennial crops depend on environmental factors, on cultivars and management practices and, in case of lowland tea, on leaf-quality criteria. More shade is required when crops are still in a singleleaf-layer stage than when a multi-layer canopy has been formed and selfshading occurs. Shade is sometimes also needed to protect full-grown leaves and branches against sun scorch. As a management tool shade can be used to reduce the photosynthesis-driven growth to levels which can be met by the nutrient supply from the soil. Shade trees are multifunctional. Apart from creating a favourable microclimate, they can increase the organic matter supply through leaf litter and prunings, thereby reinforcing the nutrient cycle of the crop and the cropping system. Ideally, shade trees should form a wide-spreading, horizontal, light-filtering leaf layer, well above the canopy of the crops (National Research Council, 1993). They should be deep-rooting to avoid root competition with the main crop and for uptake of nutrients from the deeper soil layers. Fast-growing and luxuriant trees should tolerate pruning and pollarding. Commonly used shade trees include well-known agroforestry plants such as various Acacia and Albizia species, Derris microphylla (Miq.) Jackson, Erythrina spp. (E. poeppigiana (Walp.) O.F. Cook., E. subumbrans (Hassk.) Merrill), Gliricidia sepium (Jacq.) Kunth ex Walp., Grevillea robusta A. Cunn. ex R. Br., Leucaena spp. (L. diversifolia (Schlecht.) Benth., L. leucocephala (Lamk) de Wit), and Paraserianthes falcataria (L.) Nielsen. During establishment, crops like cocoa and coffee may need lateral shade, also referred to as temporary shade. For this purpose shrubs (Flemingia macrophylla (Willd.) Merrill and Tephrosia spp.) and trees (Leucaena leucocephala) are planted in hedges along single or double rows ofcrop plants. These hedges have a secondary function: the provision of mulch. This practice, originating from plantation agriculture, has been further developed in the alley-cropping model, in which annual food crops are grown in between nutrient-cycling hedges which are pruned frequently to provide mulch for the inter-row crops. Here the emphasis is on the transfer (recycling) of nutrients from the auxiliary plants to the main crop plants, and not on lateral protection. Hedges of Gliricidia sepium

INTRODUCTION

21

T a b l e 1. Major a u x i l i a r y p l a n t s , t h e i r functions a n d occurrence in different ecological zones. Name

Auxiliary functions

Ecological zones

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03

Acacia

5

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crassicarpa

Acacia glauca Aeschynomene afraspera Albizia chinensis Albizia procera x x x x

Azadirachta Bruguiera Bruguiera Calliandra

indica cylindrica sexangula calothyrsus

Calopogonium

mucunoides

Casuarina equisetifolia Casuarinajunghuhniana Centrosema pubescens Chromolaena odorata

x x x x x x

Cordia alliodora Crotalaria micans Crotalaria pallida Crotalaria spectabilis

x x x x x

Crotalaria trichotoma Cyamopsis tetragonoloba Dactyladenia barteri Derris microphylla Desmodium adscendens Eichhornia crassipes

x x x x x x

x x

x x

x x x x x x

x x x x

x x X

(S

(semi-arid-)sub-humid-humid(-per-humid) tropics, subtropics, 0-1000 m (semi-arid-) sub-humid-humid(-per-humid) tropics, 0-400(-1000) m (semi-arid-) sub-humid-humid(-per-humid) tropics, 0-200(-450) m (arid-)semi-arid-sub-humid tropics, 0-1200 m humid tropics, 0-900 m sub-humid-per-humid tropics, subtropics, 0-1800 m (semi-arid-)humid(-per-humid) tropics, subtropics, 0-1500 m semi-arid-per-humid tropics, subtropics, (300-)1000-1800(-3000) m semi-arid-sub-humid(-per-humid) tropics, 0-700(-1500) m humid tropics, about 20 m humid tropics, about sea-level semi-arid-per-humid tropics, (0-)250-800(-1850) m sub-humid-humid tropics, (0-)300-1500(-2000) m

auriculiformis

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Acacia aulacocarpa Acacia

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semi-arid-per-humid tropics, 0-100(-1200) m semi-arid-sub-humid tropics, (0-)1500-3100 m sub-humid-humid tropics, 0-600(-900) m (semi-arid-)sub-humid-humid tropics, 0-1000(-1500) m semi-arid-per-humid tropics, 0-1000(-2000) m tropics, 0-1600(-2600) m semi-arid-per-humid tropics, 0-1000(-1800) m semi-arid-per-humid tropics, subtropics, 0-1500 m humid tropics, 0-1800 m semi-arid-sub-humid tropics, 0-900 m sub-humid tropics, 0-300 m humid tropics, 200-1200 m (per-humid-)humid tropics, subtropics, 200-1000 m tropics, subtropics

22

AUXILIARY PLANTS

T a b l e 1. C o n t i n u e d Name

Auxiliary functions

Ecological zones

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CD

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Erythrina fusca Erythrina poeppigiana

x x

Erythrina subumbrans Erythrina uariegata Eucalyptus camaldulensis

x x x

Eucalyptus tereticornis

x

Eucalyptus

S =£2 a

S S .3 43

x x

x

x x

x

x

x

x

urophylla

x

Flemingia macrophylla Gliricidia sepium Grevillea robusta Homonoia riparia Indigofera hendecaphylla

X

X

X

x

X

x x

x

x

X

x x

x x x x

X

X X

X

X X

Indigofera hirsuta Indigofera suffruticosa Ipomoea Kleinhovia hospita Kummerowia

x

Lespedeza cuneata

x

X X

X

X X

x

Leucaena diversifolia

x

x

x

Leucaena leucocephala

x

x

x

Lupinus

x

Maesopsis eminii

x

Melia azedarach

x

x x

Melilotus

x x

Mikania Mimosa diplotricha

x x x

sub-humid-per-humid tropics, 0-2000 m sub-humid-per-liumid tropics, (0-)500-1500(-2000) m humid tropics, (0-)300-1500 m humid tropics, 0-1200 m arid-per-humid tropics, subtropics, temperate regions, 20-700 m semi-arid-per-humid tropics, subtropics, 0-1800 m (semi-arid-)sub-humid-humid(-per-humid) tropics, (70-)1000-1500(-3000) m sub-humid-per-humid tropics, 0-2000 m semi-arid-per-humid tropics, 0-1500 m semi-arid-humid tropics, 130-2300 m (per-humid-)humid tropics, 50-500 m semi-arid-sub-humid(-per-humid) tropics, 0-700(-2500) m semi-arid-per-humid tropics, 0-1500 m tropics, 0-1800 m tropics, 0-800 m humid tropics, 0-200(-500) m highland tropics, subtropics, w a r m temperate regions highland tropics, subtropics, w a r m temperate regions, 1200-2200(-3100) m semi-arid-per-humid highland tropics, (700-)1000-2500 m semi-arid-humid tropics, subtropics, 0-1000 m or higher at least (250-)350 m m rainfall, tropical highlands, subtropics, temperate regions sub-humid tropics, (0-)600-900(-1800) m semi-arid-humid tropics, subtropics, temperate regions, 0-1200(-2200) m highland tropics, subtropics, temperate regions, 0-2000 m humid-per-humid tropics, 0-1500(-3000) m humid tropics, 0-2000 m

INTRODUCTION

T a b l e 1. C o n t i n u e d Name

Auxiliary functions

Ecological zones

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a o

fi

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CD

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Paraserianthes falcataria Peltophorum dasyrhachis Pongamia pinnata juliflora

Psophocarpus scandens Pueraria phaseoloides Rhizophora apiculata Samanea saman Schleichera oleosa Senna didymobotrya Senna hirsuta Senna siamea

x x X X

X X X X

X

Sesbania Sesbania rostrata Sonneratia ovata Tephrosia Candida Tephrosia purpurea Tephrosia uogelii Thespesia populnea Trema orientalis Vigna hosei Vigna marina Vigna trilobata Vigna vexillata

X

X X

X

X

X

X

X

X

X

X

X X X X

X

X X X

X X

X X

X

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Mucuna pruriens cv group Utilis

Prosopis

ca

X

(semi-arid-)sub-humid-per-humid tropics, subtropics, w a r m temperate regions per-humid tropics, 0-2300 m humid-per-humid tropics, 0-800 m semi-arid-per-humid tropics, subtropics, 0-1200 m semi-arid-sub-humid tropics, subtropics, 0-1500 m sub-humid-humid tropics, 0-950 m humid(-per-humid) tropics, 0-1000 m (per-)humid tropics, sea-level sub-humid-per-humid tropics, 0-1000 m semi-arid-per-humid tropics, 0-900(-1200) m tropics, 900-2400 m tropics, 0-700 m (semi-arid-)humid-per-humid tropics, 0-1300 m semi-arid-humid tropics, subtropics, 0-850(-1250) m tropics, 0-1600 m tropics, sea-level semi-arid-per-humid tropics, 0-1600 m tropics, 0-400C-1300) m semi-arid-per-humid tropics, 0-2100 m tropics, sea-level sub-humid-humid tropics, 0-2000C-2500) m per-humid tropics, 0-1100 m a t least semi-arid tropics, sea-level at least semi-arid tropics, 0-2100 m sub-humid tropics, ?-1200(-1500) m

23

24

AUXILIARY PLANTS

and Leucaena leucocephala are often used for this purpose. On-farm trials are essential to test the shade and alley trees, and to convince farmers of the advantages ofthe system, especially ifrewards are not immediate (UTA, 1995). In forestry, nurse trees are often planted between the main trees providing timber. Nurse trees are fast-growing and their shade not only improves the microclimate but also the shape ofthe timber trees and reduces weed growth. Roadside plants include trees planted along roads, railway lines, canals, rivers and power lines. They provide shade, play a protective role in the landscape and improve comfort during travel; they are dealt with in the volume on Ornamental Plants. Cover crops Tree and plantation crops are usually planted directly at final spacing, and therefore the inter-row soil surface needs to be protected while they are establishing. Intercropping with a mixture of cover crops is a common practice to protect the soil against erosion and to prevent soil nutrients from leaching. Cover crops help to maintain the physical properties of the soil by protecting it by lowering the soil temperature and promoting life of microorganisms in the soil, which benefits soil structure. The growth of cover crops usually declines when the tree canopy closes. Sun-loving species disappear first, shade-tolerant species last. Mature oil-palm plantations contain few or no cover crops or weeds on the ground. Rubber plantation canopies allow more light to reach the soil surface (at least periodically), but a luxuriant ground cover is a disadvantage, as it interferes with the daily latex harvest. Unlike green manure crops, cover crops are not ploughed or dug in. Important cover crop species include Calopogonium mucunoides Desv., Centrosema pubescens Benth. and Pueraria phaseoloides (Roxb.) Benth. Velvet bean {Mucuna pruriens (L.) DC. cv. group Utilis) has become a popular cover crop with farmers in West Africa. Its advantage is that it enriches exhausted soil with nitrogen in only one or two seasons, and takes up whatever phosphate is available (UTA, 1995). The presence of suitable strains of Bradyrhizobium bacteria or of vesicular-arbuscular mycorrhizae (VAM) should be verified if initial growth is slow in a particular area, as successful growth depends on atmospheric nitrogen fixation and efficient nutrient uptake. A good Mucuna crop smothers Imperata grass and shades out unwanted weeds (UTA, 1995; Versteeg &Koudokpon, 1990). Low-growing cover crops can be grown as live mulch (UTA, 1995). Ideally, they do not compete substantially with the main crop where soil moisture is adequate during the growing season. Green manures Green manure and cover crops are both sown or planted in situ, but the former are ploughed in at an appropriate time. All plants, whether leguminous or not, that enrich the soil with organic matter and nutrients when incorporated in the soil, provide green manure if their residues contain no allelophatic substances. Certain species are particularly useful. These include herbaceous plants which can be worked into the soil before they complete their life cycle,

INTRODUCTION

decompose rapidly and release nutrients which become available for the associated crops. Their ability to fix atmospheric nitrogen and their high content of this element make most legumes important green manures. Other desirable characteristics of suitable green manure crops are easy establishment and rapid production of large quantities of green biomass, and a well-developed, deep root system. They should not be host plants for diseases and pests affecting the main crops. The main function of green manures is chemical improvement of the soil, but beneficial effects on soil biology and soil physical properties are also well documented. Because green manures consist of readily decomposable material, their effects on lowering soil temperature and conserving soil moisture, are of short duration (Tian, 1992). Green manures include cultivated and wild annual and perennial legumes. Calopogonium mucunoides, Pueraria phaseoloides and Vigna hosei (Craib) Backer are among the most widely used green manures. Other examples of tropical green manures are guar (Cyamopsis tetragonoloba (L.) Taubert), cowpea {Vigna unguiculata (L.) Walp.), Crotalaria spp. and Sesbania spp. Many species have been tested in the past, but few have shown promise (Botton & Halle, 1957, 1958;Keuchenius, 1924). Green manure can be grown in a rotation with other crops, in a simultaneous association with the main crop (Singh, 1984) or as a relay crop. As rotation crops, they are worked into the soil before sowing the next crop. Green manures may compete with short-duration pulses. When soil moisture is adequate for a short-duration pulse, farmers will plant the latter. When water supply is only assured for less than two months, then green manures are preferred. When farmers lack resources to grow pulses over large acreages as catch crop, green manure legumes may dowell (Singh, 1984). Before being incorporated into the soil green manure may be sown directly in a given field, or grown first on the bunds or nearby wasteland to be cut and transported to the selected field later on ('cut and carry system'). Many species have been reported as being useful as green manure. Several of these just happened to grow as weeds, were ploughed in and found to provide organic matter, without further verification of whether they are better than other species. Some ofthem are included in this volume. Mulches Plants used as mulches are treated differently from green manures. Their leaves and branches (green or dried) are removed and placed on the soil where physical protection of the surface soil is required, and left to decompose, sometimes eventually to be ploughed in. During decomposition organic matter and nutrients are added to the soil. Plant material with good mulch properties is characterized by a high C/N ratio and a high lignin content (Tian, 1992). Applied to the soil it decomposes slowly and can thus provide a long-lasting soil cover. Mulches are mainly used to protect the soil surface. Many plants can be cut or pruned, and the prunings can be spread over the soil in a layer. The benefits include a reduction in soil temperature, and a more optimal soil biology, less evaporation and erosion and prevention of mud splashing on vegetable

25

26

AUXILIARY PLANTS

products. Temperatures in the upper 5 cm of soil mulched with Leucaena leucocephala, Gliricidia sepium, and Flemingia macrophylla, respectively, were lowered by 2.9°C, 4.6°C, and 6.6°C compared to the control (37.1°C) unmulched soil. The soil moisture under these mulches during a period of 60 days was 7.1%, 8.7% and 9.4% compared to 4.8%observed in unmulched soil (Budelman, 1991). Some of the worst weeds such as Chromolaena odorata (L.) R.M. King & H. Robinson make good mulch provided plants are cut prior to flowering (Slaats, 1995). Mulching with material containing seed is an effective way of introducing a major weed problem. The introduction of the agroforestry techniques of alley farming or hedgerow intercropping has renewed interest in the potential of using prunings from fast-growing shrubs and woody species for mulch. The legumes Gliricidia sepium, Leucaena leucocephala and Senna siamea (Lamk) Irwin & Barneby are particularly interesting. Their prunings have more of the characteristics of green manure: they are succulent, rich in nitrogen, decomposing rapidly, and enriching the soil. Fallow crops Auxiliary crops are used in fallow systems to improve the plant nutrient supply for subsequent crops, to improve the physical conditions of the soil, to suppress weeds (especially grasses) and/or to provide income. Fast-growing leguminous trees have several advantages as a fallow compared with the naturally regenerating vegetation. For example, Sesbania sesban (L.) Merrill is grown for one to two years as a fallow crop in maize cropping systems in southern Africa to accumulate nitrogen in the biomass, to smother weeds and to provide poles and firewood (ICRAF, 1993). However, caution should be observed in selecting planted fallow species. Plants like Sesbania sesban harbour root-knot nematodes which may be harmful to certain crops, in particular root and tuber crops. In alley-cropping trials with a one year fallow period in which the trees are left unpruned, shading has proved to be effective in weed control. Alley cropping with Leucaena leucocephala resulted in a shift from fast-growing annual weeds characteristic for frequently cropped fields to shade-tolerant and less competitive weeds (Akobundu et al., 1995). In areas in which weed control is an important consideration (e.g. in Imperata grasslands) Peltophorum dasyrhachis (Miquel) Kurz, with its dense umbrellashaped canopy, appears to be promising for low-cost reclamation of weed-infested land and also as a woody component of alley cropping (van Noordwijk et al., 1992). In long-term trials in farmers' fields in Benin, West Africa, short velvet bean (Mucuna pruriens cv. group Utilis) fallows have proved to be very effective in smothering Imperata and improving soil fertility (Versteeg & Koudokpon, 1994). An interesting research finding in the 1920s and 1930s in North Sumatra, Indonesia was that a fallow crop of Mimosa diplotricha C. Wright ex Sauvalle was rather effective in reducing bacterial wilt disease caused by Pseudomonas solanacearum in a subsequent tobacco crop (Wiersum, 1983). However, the effect appeared to be only modest when the fallow period was not longer than about 8years (Van der Laan, 1949).

INTRODUCTION

Live fences Around houses, farms or fields and along roads, live fences serve the useful role ofphysically separating areas. These fences are sometimes managed as hedges, i.e. are pruned and pollarded. Live fences mark boundaries between properties, contain or exclude livestock, and provide shade, fuelwood, fodder, mulch material or green manure. Suitable species for live fences includeAcacia spp., Casuarina spp., Leucaena spp., and Tithonia diversifolia (Hemsley) A. Gray. Ornamental species are often used in hedges near houses. These are mainly dealt with in the volume on Ornamental Plants, however. If properly established, hedges can avoid high costs of erecting non-living fences, and may prove very economical in maintenance. Their role as fodder bank may be considerable, especially during the dry season. An inedible hedge, e.g. of'Euphorbia tirucalli L., provides protection from browsing livestock. Hedges should be pruned regularly, to keep them at a manageable size. Wind-breaks and shelter-belts Wind-breaks are strips or rows of trees and shrubs that are planted very closely together along the edges of a field or garden to protect crops and soil from the detrimental effects of wind. Sometimes they are planted on a much larger scale in semi-arid regions to protect areas against desertification. Strong, or hot and dry winds blowing from a predominant direction, are alleviated by fences planted windward to the field. Very few species are grown solely as a wind-break. Usually this role is combined with other uses such as providing shade, fuelwood, fodder, or green manure. Live fences withstand pruning, and the prunings can be fed to livestock if palatable, or used as green manure or mulch. The species most used, combined with the latter two purposes, is probably Leucaena leucocephala. Other species commonly used for wind-breaks and shelter-belts in South-East Asia are Casuarina equisetifolia L., C.junghuhniana Miquel, Erythrina variegata L. and Gliricidia sepium. Flemingia macrophylla is a successful wind-break on steep slopes in the Philippines. Erosion-controlling

plants

The areas rendered unpractical for cultivation for reasons of erosion, or those prone to erosion due to the slope of the terrain, can be protected by species that have good rooting properties to fix the soil. To cover waste areas a pioneering habit forming a dense ground cover is required. This may be a disadvantage as plants with these characteristics, such as Mimosa diplotricha, run the risk of becoming noxious weeds. Tephrosia purpurea (L.) Pers. is less invasive. Cyperus spp. produce many seeds and some species have long stolons that form an underground mat which holds the soil. The well-known beach plant Ipomoea pes-caprae (L.) R. Br. binds sand and helps combat wind erosion. Vetiveria zizanioides (L.) Nash, a coarse perennial grass, is now widely used in the tropics to protect contours. Harvesting its roots containing an essential oil, however, may be a major cause of erosion. Therefore, its cultivation for erosion control was prohibited in Java. Wet or dry,

27

28

AUXILIARY PLANTS

sandy or compacted wastelands can be seen covered with various plants, such as Cyperus spp., but this is most undesirable with nutsedge (Cyperus rotundus L.), the most notorious weed in the world (Holm et al., 1977). When the pioneer role has been fulfilled, these sedges can be replaced by other plants. Land reclamation species Vast areas of wastelands such as abandoned open mines and mine spoils and eroded land have been used with limited success for agriculture in South-East Asia, as they require high inputs ofcapital and labour for rehabilitation. Auxiliary plants have been shown to improve the properties of soils on these difficult sites. Chemically they will increase the organic carbon and nutrient contents of the soils and improve the pH. The physical properties of the soil, such as its water-holding capacity, are improved by the good soil cover and accumulation ofleaf litter provided by fast-growing auxiliary plants. Furthermore, their usually dense and shallow root system make such plants suitable for stabilizing eroding land. Acacia crassicarpa A. Cunn. ex Benth. has shown outstanding potential in land reclamation and soil improvement in a wide range of degraded sites in the subhumid and humid tropics, as do A. auriculiformis A. Cunn. ex Benth. and A. mangium Willd. in the rehabilitation of tin tailings in Malaysia and Imperata grassland in Indonesia. These species and also A. aulacocarpa A. Cunn. ex Benth. produce numerous root nodules, survive on land low in organic matter and nitrogen where most other species fail, and are able to suppress Imperata grass, thus making them useful reclaimers. Live supports and stakes Many food and spice plants are climbers that need support from poles or trellis to economize space and induce flowering. Pepper (Piper nigrum L.) and betelvine (P. betle L.) cultivation is unthinkable without plant support. Erythrina spp. are good examples for live supports. Gliricidia sepium and Leucaena leucocephala are other examples of live stakes for yam cultivation in Africa (Budelman, 1991). Maize and sorghum serve as live support for beans, but obviously that is not their primary role. Bamboo poles may be used to stake vegetables. The material used to make trellis is rarely specified. Fuelwood (firewood and charcoal) From many studies on forecasting the demand and supply offuel sources it appears that fuelwood will be a necessary commodity in South-East Asia, at least for the rural economies, for many decades to come. Fuelwood plantations will play an increasingly important role in this, if forests are to be managed in a sustainable way. Crop residues, particularly from woody species (e.g. Cajanus cajan (L.) Millsp., even stems of cassava (Manihot esculenta Crantz) are becoming more valuable in the provision of firewood. Fuelwoods are often planted in marginal areas, where they also protect the land against degradation and erosion. Those woody species that can be grown

INTRODUCTION

in agroforestry or forestry systems to produce firewood have a definite service role as well. Timber species from which fuelwood is obtained by pruning of branches or thinning, are not included in this volume, however, and roadside trees have been included only if their firewood or protective role are important. Mangrove species ofAvicennia, Bruguiera and Rhizophora are important as fuel; because of excessive cutting, the protection afforded by mangroves to many low-lying coastal areas in the tropics is threatened. The mangrove swamps are economically important sources of crustaceans (shrimps, crabs and lobsters), are nursery grounds for many species of fish and house many sea birds and other wildlife. Conservation of the mangrove forests is urgent; the mangrove vegetation near centres of population has sometimes been entirely consumed for firewood. Fast-growing trees for communal fuel plantations are becoming increasingly important (e.g. in Thailand, Nepal), but are not a universal panacea. The private cultivation of trees for firewood is also increasing. Species commonly used for fuelwood include Acacia auriculiformis, Calliandra calothyrsus Meisner, Casuarina equisetifolia, Eucalyptus camaldulensis Dehnh., Gliricidia sepium and Prosopis spp. Firewood is used not only for the domestic purposes of cooking, and in hilly and mountain areas for heating, but also supplies energy for rural industries (Bhattacharya, 1986; Smiet, 1990), even when fossil fuels are available. In Java, 90% of all fuelwood is used for domestic purposes. This island has a centuries-old tradition of agroforestry. About 3 million ha are under agroforestry, which provides fuel for more than 100 million people. Only 10%ofthe fuelwood is supplied by natural forest (Smiet, 1990). In the Philippines, 60 000 ha ofwood-energy plantations have been established since 1979. It is government policy to substitute wood for imported fuel for some industrial processes, in order to reserve more fuelwood for the growing population, but it is planned to generate power for rural electricity grids in 60-70 plants using firewood. Tall Leucaena leucocephala cultivars are used in 90% of the total area planted. Reported annual growth rates range from less than 20 m 3 (8t) to 90 m 3 (36 t) per ha, less for coppice crops. Harvests are taken after 3-5 years (Perlack et al., 1995). Although the importance of domestic fuel in Malaysia has declined due to the considerable increase in the standard of living, rural people still use firewood and charcoal as a source of energy. These fuels are also consumed in substantial amounts in the manufacture of bricks, roof tiles, pottery, for the curing of tobacco, and in sawmills with kiln-drying facilities. Most ofthe charcoal is used in steel mills. In Peninsular Malaysia alone, the average annual consumption from 1972 to 1978 was 34 008 m 3 firewood and 163 569 m 3 charcoal (average of 1972, 1974, 1976 and 1978) (Wong & Kader, 1980). The most popular Malaysian fuelwoods are Bruguiera spp. and Rhizophora apiculata Blume. Three large areas in Malaysia are managed sustainably for the production of charcoal and firewood: Matang (Perak), Kelang (Selangor) and South Johor. The Matang mangroves have the reputation of being the best managed in the world (Frisk, 1984). In Vietnam, about 75%of the total energy consumed is contributed by biomass fuel. The proportion in the domestic sector is nearly 100%. This includes about 45% fuelwood and 55%residues (Ministry ofForestry, 1992).

29

30

AUXILIARY PLANTS

Burma (Myanmar) also relies heavily on biomass-based fuel: about 85% of the total amount of energy is provided by firewood and charcoal. As in Thailand, bamboo provides good fuel. As the rotation cycle of bamboo is usually shorter than for other fuelwood, the use of bamboo will diminish pressure on other sources ofbiomass fuel (Bhattacharya, 1986;U Saw Thun Khiang, 1993). Other more recent estimates on the share of biomass in the total energy consumption for South-East Asia are presented in Table 2, some differing from the values given above. Some wood is particularly suitable for charcoal. Casuarina equisetifolia and C.junghuhniana, for example, are widely used in Thailand. Rhizophora mucronata Poiret produces excellent charcoal too. Charcoal is preferred in many households in South-East Asia particularly in the slightly more affluent urban ones. It has a higher energy value than plain firewood, provides higher temperatures for industrial purposes (such as for smithies), is cheaper and easier to transport and provides cleaner cooking (less smoke). Water-clearing agents Domestic and industrial waste water may be treated by biological means: many microbial agents and water plants purify water by producing oxygen and taking up inorganic substances, even including heavy metals. Small amounts of drinking water can be purified by adding vegetal products. These products are traditionally used in Africa and on the Indian subcontinent; their use is limited in South-East Asia. Flocculating agents or coagulants that clean water include crushed seeds of Moringa oleifera Lamk (Folkard & Sutherland, 1996), dried leaves of Strychnos colubrina L., and gum of Anacardium occidentale L. or Lannea coromandelica (Houtt.) Merrill that clarifies cane sugar or palm sugar juice e.g. in Indonesia (Jahn, 1988). Larger amounts of domestic or industrial waste water can be treated by channelling it into basins, water courses or lakes where water plants act as biological clearing agents (National Academy of Sciences, 1976). Common aquatic weeds in swamps can clean waste water. Situations where water moves slowly are ad-

Table 2. Share ofbiomassinthetotal energyconsumption(%). Share ofbiomass(%) Burma (Myanmar) Cambodia Indonesia Laos Malaysia Papua NewGuinea ThePhilippines Thailand Vietnam n.a.=not available Source:FAO(1996).

80- 90 n.a. 40- 50 90-100 0- 10 n.a. 40- 50 20- 30 50- 60

INTRODUCTION

vantageous for biological cleaning. Reeds (e.g. Phragmites australis (Cav.) Trin. ex Steudel), rushes (e.g.Scirpus lacustris L.), water hyacinth {Eichhornia crassipes (Martius) Solms), Nile cabbage (Pistia stratiotes L.) and submerged plants such as Ceratophyllum demersum L. take up nitrogenous and phosphorous compounds, harbour active microbial organisms and render the water safe for release to rivers or for use (or re-use) as domestic water. Anaerobic conditions should be avoided, by maintaining a partially free water surface or feeding oxygenated pretreated water to the weed-filled treatment ponds. Plants that have treated raw sewage must be disposed of safely. Water hyacinth can be fermented to methane gas. In situ water clearing, even if not yet practised deliberately, occurs in all water courses with abundant plant life. In Belgium, dirty water from the Schelde river is treated in shallowly flooded reed beds. In the Netherlands, long ditches in which reeds grow reduce the investments and operating costs of activated sludge installations by 75%or more (de Ridder, 1996). Water purification should only be tested with species present in the area, and never with newly introduced species, as water weeds are among the most dangerous weeds (National Academy of Sciences, 1976). 1.2.2 Importance It is difficult to make sweeping statements about the actual role of auxiliary plants in terms of economic benefit, as statistical information is lacking. Only the value or tonnage offuelwood can be estimated to a certain degree, using data from experiments (National Academy of Sciences, 1980). The fact that more than half ofthe world population depends on fuelwood for cooking, and that the consumption of fuelwood is still rising (FAO, 1994), illustrates the importance ofthis commodity. The actual role of soil-protecting and soil-improving auxiliary plants is quantified in field experiments where the soil nutrient status and yield before and after the introduction of auxiliary plants have been measured. In some cases the effects are negative e.g. as a result of competition for resources between auxiliary and main crop plants and the overexploitation of the production function of the auxiliary plants. Possible yield losses of the main crop might, however, be compensated by these secondary products. Auxiliary plants are important in maintaining soil fertility in the plantation agriculture of South-East Asia. This effect is such that soils are still highly productive even a hundred years after the forest vegetation has been cleared, even in areas with high rainfall and sloping land. However, over-exploitation and removal ofproducts may result in nutrient mining and degradation ofthe soil. Establishing contour strips of auxiliary shrubs and trees on slopes and then cultivating along the contours is an effective technique for erosion control. In the Philippines, this concept has been developed for farmers' use in the socalled 'SlopingAgricultural Land Technology' (PCARRD, 1986). As long as land resources are adequate, improved fallows permit the fallow period to be shortened without much loss ofyield and so contribute to intensification of production. Atmospheric nitrogen fixation is an prominent attribute of the important category of leguminous auxiliary species. In many cropping systems the amount of

31

32

AUXILIARY PLANTS

N supplied by legumes corresponds to at least 50 kg/ha per year. Generally speaking, farmers are only willing to adopt auxiliary crops if the rewards of the new practice appear substantial enough to make it worthwhile relinquishing traditional cropping practices. It is difficult to motivate farmers, particularly if the rewards are delayed, and show up in the productivity of subsequent primary crops (UTA, 1995). Participatory experimentation in these technologies as part of on-farm testing is essential, but many practical difficulties are involved (Versteeg &Koudokpon, 1994). 1.2.3 Selection of species Plants having a service role as their primary use have been selected for inclusion as major species in this volume (Chapter 2);others are dealt with as minor species (Chapter 3). Mention has been made of the auxiliary role of plants in other commodity groups (Chapter 4), but only occasionally is such a species given a full treatment focusing on the service task (e.g. some forages). 1.3 Botany 1.3.1 Taxonomy A large majority of the species dealt with in this volume are Dicotyledons. A few Gymnosperms (Pinus caribaea Morelet and other spp.), which are potentially ofinterest for reclamation purposes, are covered in the volume on Timber Trees. The major family harbouring plants with an auxiliary role is the Leguminosae. Table 3 shows that about 56% of the species treated in this volume as auxiliary plants are Leguminosae. The most recent taxonomie classification has been followed, in accordance with international usage. Therefore several well-known Cassia species now have to be referred to as Senna or Chamaecrista species. The former subgenera in the large genus Cassia L. sensu lato have been elevated to genera, a taxonomie decision backed not only by morphology, but also by molecular and microbial data. However, it has been decided not to follow the split in Acacia L. in this volume, although this very large genus may well merit subdivision into several genera. This new classification ofAcacia has only been carried out for the Australian species (Pedley, 1986), and this drastic step has met with some opposition. The genus Racosperma C. Martius has been reinstated, and the new combinations are listed in the relevant treatments as synonyms. 1.3.2 Growth and development Certain characteristics ofplants with different service functions are known; for instance, unbranched, rapidly growing stems are useful for trees producing stakes, prolific branching is useful for hedges, multiple stems produce firewood easy to fell, and rooting habit is important for cover crops. Fast growth is generally required. Good regeneration and coppicing abilities are major attributes for many plants in this commodity group. However, little is known about the growth and development of most auxiliary plants. Whatever information has become available is presented in the species treatments.

INTRODUCTION

Table 3. Plant families contributing auxiliary plants. Family

Major auxiliary plants

Minor auxiliary plants

Total number

Actinidiaceae Casuarinaceae Ceratophyllaceae Compositae Convolvulaceae Cyperaceae Eriocaulaceae Euphorbiaceae Gramineae Leguminosae Caesalpinioideae Mimosoideae Papilionoideae Meliaceae Myrtaceae Proteaceae Rhizophoraceae Scrophulariaceae Other families

Total

11

2 1 4 13

6 7 2 10 4 7 5 2 10 120 11 29 80 2 3 3 4 4 24

91

122

213

2

3 3

1

62 4 13 45 2 3 1 3

-

6 5 2 7 1 7 5 1 10 58 7 16 35

% 2.8 3.3 0.9 4.7 1.9 3.3 2.4 0.9 4.7 56.3 5.2 13.6 37.5 0.9 1.4 1.4 1.9 1.9 11.3

100

1.3.3 Atmospheric nitrogen fixation and mycorrhizae Atmospheric nitrogen-fixing

organisms

Many ofthe auxiliary plants are associated with atmospheric nitrogen fixation, the reason why many cropping systems persisted to support reasonable levels of food production over the centuries without the addition of much fertilizer. Four groups of nitrogen-fixing organisms useful to plants can be distinguished (see also Table 4): root and stem-nodulating rhizobia, cyanobacteria (bluegreen algae),Frankia species, and free-living nitrogen-fixing agents. - Root and stem-nodulating rhizobia Rhizobia, the root-nodulating (Bradyrhizobium and Rhizobium spp.) and the stem and root-nodulating (Azorhizobium caulinodans) bacteria, that form symbiotic associations with Leguminosae and Ulmaceae, are the main group of nitrogen-fixing species. In waterlogged conditions the associations between Aeschynomene spp. and Bradyrhizobium and between Sesbania rostrata Bremek. & Oberm. and Azorhizobium caulinodans and Bradyrhizobium are particularly interesting. Classification of these bacteria has made great strides in the last decade (Holt et al., 1994; Sprent, 1994; Sprent &Sprent, 1990;Woese, 1987). Sole crops of grain legumes in the tropics may fix from a few kg up to 200 kg N/ha annually in widely different cropping systems (Giller & Wilson, 1991). Trees and shrubs may fix up to about 270 kg N/ha per year, but here assess-

33

34

AUXILIARY PLANTS

Table 4. Nitrogen-fixing organisms useful in plants. Nitrogen-fixing organism

Host plant

Root-nodulating rhizobia Brady rhizobium japonicum Bradyrhizobium sp. Rhizobium galegae Rhizobium leguminosarum biovar. phaseoli biovar. trifolii biovar. viciae Rhizobium loti Rhizobium meliloti Rhizobium tropici

soya bean cowpea Galega Phaseolus beans clover Pisum, Vicia Lotus Medicago, Melilotus Leucaena, Phaseolus

Stem-nodulating rhizobia Azorhizobium

caulinodans

Sesbania rostrata Bremek. & Oberm.

Cyanobacteria (blue-green algae) Anabaena Frankia spp.

Azolla (e.g.A. pinnata R. Br.) Alnus,Allocasuarina, Casuarina, Dryas, Elaeagnus, Gymnostoma, Myrica

Free-living nitrogen-fixing agents Acetobacter diazotrophicus Azospirillum lipoferum

sugar cane grasses

Sources:Jones &Lewis, 1993;Sprent &Sprent, 1990.

m e n t of r e s t r i c t e d root s y s t e m s m a y n o t reveal t h e e n t i r e p i c t u r e . Denselyp l a n t e d saplings ofLeucaena leucocephala m a y a c c u m u l a t e 5 0 0 - 6 0 0 k g N / h a in t h e a b o v e g r o u n d m a s s a n n u a l l y , b u t t h e s e a m o u n t s a r e n o t d u e to n i t r o g e n fixation alone. It should be recalled t h a t it is notoriously difficult to q u a n t i t a t i v e l y record a n d s t a n d a r d i z e a t m o s p h e r i c n i t r o g e n fixation. A n n u a l or short-lived p e r e n n i a l l e g u m e s a r e i m p o r t a n t for t h e i r role i n r o t a t i o n s if crop r e s i d u e s a r e left in or r e t u r n e d to t h e field, or a t l e a s t t h e root m a s s is left b e h i n d , or w h e n t h e s e species a r e deliberately g r o w n a s g r e e n m a n u r e . I n agroforestry t h e benefits a r e u s u a l l y from leaf l i t t e r a n d ecological protection (shade, w i n d - b r e a k ) b u t t h e y m a y be offset by competition for light, wat e r a n d n u t r i e n t s . I n t h a t case, p r u n i n g t r e a t m e n t s a r e called for (see 1.5.3). Tropical p a s t u r e l e g u m e s h a v e p r o v e n t h e i r v a l u e for n i t r o g e n fixation, carbon s t o r a g e a n d a n i m a l production ('t M a n n e t j e , 1997). T h e u s e of n i t r o g e n fixing l e g u m e s is well e s t a b l i s h e d in A u s t r a l i a a n d t h e r e is r e a s o n a b l e adoption in p a r t s of S o u t h - E a s t Asia a n d L a t i n America. However, m a n y count r i e s , p a r t i c u l a r l y in Africa, h a v e p r o b l e m s r e l a t e d to l a n d t e n u r e , i n f r a s t r u c t u r e a n d social j u s t i c e t h a t n e e d to be solved first before i m p r o v e m e n t s in a g r i c u l t u r a l production c a n t a k e place.

INTRODUCTION

Symbiotic nitrogen fixation by legumes is also important for phosphate nutrition. As a result of the availability of symbiotically fixed nitrogen, the plants will absorb more cationic than anionic nutrients. This uptake pattern causes the vicinity of the absorbing roots to acidify, and 'unavailable' soil phosphates and added rock phosphates may partially solubilize. As a result, leguminous plants are more efficient in phosphate uptake than, for example, cereals (Aguilar Santelises, 1981). Auxiliary leguminous plants can thus indirectly contribute to the phosphate nutrition of the main crop through leaf litter decomposition. There is also experimental evidence that P absorption of legumes can be enhanced further when vesicular-arbuscular mycorrhizae are active in addition to rhizobium bacteria (Aguilar Santelises, 1981). Cyanobacteria (blue-green algae) The second most important group of atmospheric nitrogen fixers covers the cyanobacteria (the blue-green algae), both the free-living ones and those associated with plant species, notably the aquatic fern Azolla, that harbours Anabaena azollae (Whitton, 1993). Freeliving cyanobacteria can be cultivated and added to soils, the so-called algalization of rice paddies. In India, some two million ha are treated with mixtures of Anabaena, Aulosira, Nostoc, Plectonema, Scytonema and Tolypothrix. The inoculum is prepared in shallow open-air trays in which farm soil, superphosphate, starter inoculum and some insecticide are mixed. Lime is added to adjust the soil pH to 7.0-7.5. The cyanobacterial mat develops within 20 days and is then allowed to dry, producing flakes that can be harvested to inoculate the rice fields, typically about one week after transplantation of the seedlings. Atray of 1.6 m2 provides sufficient inoculum for 1ha. Preliminary results from Taiwan and Japan have not been as promising as in India, suggesting that prospects appear to be better in warmer regions. Local inocula may be more suitable than those introduced from other regions. The regional specificity of cyanobacterial strains needs to be verified by research (Whitton, 1993). Of the six species of the microphyllous ferns, the only Azolla species used for agricultural purposes to date isA.pinnata R. Br. It is currently used in Thailand, North Vietnam, and China. In rice paddies, Azolla can accumulate 25-170 kg N/ha annually (Rikuchi et a l , 1984), an average of 30 kg N per rice crop (Watanabe et al., 1977).Azolla requires particular conditions, which often restrict its applicability to certain areas. Permanent ponds are needed to maintain inocula, and high temperatures (30°C is optimum) and light intensities are generally not tolerated. Under proper conditions, Azolla spp. multiply rapidly: the population may double in two up to ten days in the field. Azolla-Anabaena combinations suitable for tropical conditions have to be selected; in ChinaAzolla-rice cultivation occurs in 2%ofthe total 34 million ha used for rice. Competition with free-living bacteria, grazing and increased disease incidence under high temperatures are explanations for suboptimal performance. Rice cultivars less demanding of nitrogen fertilizer are often successfully grown withAzolla alone without fertilizer input (Whitton, 1993). In the Philippines, a Bangkok strain ofAzolla pinnata has been tested in the South Cotabato area and found to be successful: analysis after some years showed that up to 50 kg of fertilizer per ha was saved, and less labour was required to apply Azolla than to apply fertilizer (Watanabe et al., 1977). Azolla will be dealt with in the volume on Cryptogams.

35

36

AUXILIARY PLANTS

- Frankia species A third important group in nitrogen fixation comprises Frankia species (Actinomycetes) grown in association with several woody species of some families like the Casuarinaceae, Myricaceae and the Rhamnaceae, which include perennials particularly important in agroforestry. This group has attracted interest relatively recently, and research in this field is increasing. Young Casuarina trees in symbiosis with Frankia have been found to fix 40-60 kg N/ha annually, but lower figures are also occasionally reported. - Free-living nitrogen-fixing agents It is extremely difficult, if not impossible, to estimate the amounts of atmospheric nitrogen fixed by free-living N-fixing agents such as Acetobacter and Azospirillum present in the rhizosphere of plants. The amounts do not seem to surpass 5kg N/ha per year; this is mainly observed in grassland. For a review of the last hundred years of atmospheric nitrogen fixation research, see Bothe et al. (1988). Mycorrhizae The specific mycorrhizal associations of auxiliary crops are still largely unknown. Potentially, mycorrhizae can increase the efficiency of nutrient uptake of the auxiliary host plants. An interesting observation is that the P uptake of leguminous plants growing on soils with low P levels or on soils to which barely soluble rock phosphate has been applied can be improved by vesicular-arbuscular mycorrhizae (Aguilar Santelises, 1981). This implies that the often yieldlimiting plant nutrient phosphate can be given in the cheap form of rock phosphate, and that when auxiliary crops are used, the crop-mycorrhiza association will not deplete assimilates at the expense of the main crop. For a recent review of the mycorrhizal associations in agriculture, forestry and horticulture, see Mitchel (1993). The finding that most indigenous trees in the tropical rain forest have vesicular-arbuscular mycorrhizae suggests that research on mycorrhizal associations in auxiliary tropical tree species is worthwhile. 1.4 Ecology Climatic and soil conditions are important not only for the growth and development of the auxiliary crop in question, but also for the feasibility of its specific service function. The situations in which auxiliary plants are used vary widely, and hence the microclimate also differs accordingly. Auxiliary plants may influence microclimate by moderating the climatic factors, when grown as hedges, wind-breaks, shade trees and cover crops. An overview of the ecological zones in which the most important auxiliary plants are grown is presented in Table 1. 1.4.1 Ecological interactions The degree and type of interaction depend on the proximity of auxiliary plants and main crops in time and space. Sequential and simultaneous associations of auxiliary plants and main crop plants can be distinguished (Sanchez, 1995).

INTRODUCTION

Sequential

associations

In sequential associations the growth of auxiliary plants and main crops peaks at different times. In this case auxiliary plants usually enhance the growth of the main crop by improving the soil conditions. Herbaceous plants, shrubs and trees established as an improved fallow accumulate nutrients (and in the case of some leguminous species may also fix atmospheric nitrogen) which are released to subsequent crops through clearing and burning and the decomposition ofnon-burnt material. Important attributes of fallow crops are easy establishment, rapid soil coverage, vigorous growth, deep rooting, no pest problems and, preferably, atmospheric nitrogen fixation. Easy removal and limited or no regrowth as a weed are also desired. Improved fallows are only a relevant option if farmers own their land or have secure land tenure and can afford to stop cropping on part of it. Compared to natural fallows, improved fallows should either allow the fallow period to be shortened without reducing subsequent crop yields, or result in higher yields when fallowing for the same period. Compared to continuous cropping, yields after fallowing should be high enough to more than compensate for the yields forgone in the non-cropping period and for the costs of establishing and clearing the fallow vegetation. Improved fallows are especially attractive for farmers if they produce valuable products. However, appreciable removal of these products may interfere with the nutrient accumulation in the vegetation and topsoil. The use ofLeucaena leucocephala by farmers in the Philippines is an example of an improved fallow with auxiliary plants. This leguminous tree enables fallow periods to be reduced from 6-8 to 2-4 years without depressing subsequent yields ofcrops like rice and maize (MacDicken, 1991). A transition between sequential and simultaneous associations is the use of cover crops in oil palm and rubber plantations. Cover crops are usually established 1-2 years before the main crop is planted. A few years later, by the time that competition for water and nutrients is becoming a serious problem, the cover plants phase out because of lack of light. The 4-5 year cover crop period, however, is long enough to enrich the soil with nitrogen, to recycle substantial amounts of nutrients for later use by the plantation crop and to provide favourable conditions for root development. In Malaysia, the combined action of these factors has been found to have a long-lasting positive effect on rubber yields (Broughton, 1977). Another transitional type of association occurs when during the cropping season annual crops are interplanted with auxiliary fallow plants which are removed at the beginning of the next cropping season the following year. Research in Zambia (Sanchez, 1995) has demonstrated that relay intercropping maize with Sesbania sesban gives yields double those obtained when maize is the sole crop, whether or not fertilizer is applied. In this system Sesbania sesban reseeds itself. Initially, it grows slowly and hardly competes with the maize plants but later it grows fast and ultimately yields about 1.8 t fuelwood per ha annually. A two-year Sesbania fallow gave double maize yields over a six-year period in comparison with continuous maize production without fertilizers.

37

38

AUXILIARY PLANTS

In south-western Ivory Coast, similar use is made of Chromolaena odorata, which has replaced the natural forest fallow vegetation on many sites. After a 2-4-year-old Chromolaena vegetation is slashed and burnt, one crop ofmaize is grown, while Chromolaena seedlings and sprouts from Chromolaena stumps quickly re-establish the new fallow vegetation (Slaats, 1995). It can be concluded that in sequential associations the interactions between the components ofthe system are mainly positive. Simultaneous

associations

In all simultaneous associations, sharing of space and of the resources light, nutrients and water occurs. If one or more of these resources is in short supply, species compete unless they can occupy a different part of the same niche. This niche differentiation occurs, for example, in combinations of shade-tolerant crop plants and taller auxiliary plants. In this case, sharing of light is, in principle, beneficial for the output ofthe system, provided that nutrients and water are not limiting. The effect of shade on companion crops is very complex. It involves the reduction in light intensity, temperature and air movement and it affects relative humidity and soil moisture. Reduction in light is a very important effect, as radiation is one of the main factors governing photosynthesis. In a crop like cocoa in which the photosynthetic rate of individual leaves declines at light intensitites greater than 30% full sunlight, shade is needed, especially when young trees still have a single layer of leaves. The light requirements increase as trees start to develop a closed canopy with several layers of leaves. With higher light intensities the demand for nutrients also increases. This relationship between light and nutrition also means that shade can be used to balance nutrient demand and supply on less fertile soils. In addition to improving microclimate and light utilization, shade trees can contribute to improved nutrient cycling and to the supply oforganic matter and nitrogen (see 1.4.2). In a crop like cocoa, where the presence of shade trees generally improves the output of the system, the interaction between the components can be described as complementary. Interactions in associations with species that do not tolerate shade have especially been investigated in alley cropping. In these agroforestry systems, food crops are grown between hedges of nutrient-cycling trees or shrubs which are periodically pruned during the cropping season to reduce shading and to provide green manure or mulch for the food crops. Fast-growing leguminous auxiliary species such as Gliricidia sepium and Leuceana leucocephala are often tested in experiments, using alleys about 4m wide. As a rule, the effects of prunings on crop yields, including the effects of nutrients and mulch, have been found to be positive and any negative shading effects have been minor when hedge plants are timely pruned. The subterranean sharing of resources, however, has often adversely affected crop growth, especially in semi-arid areas where soilmoisture is limiting (Ong, 1994). On the basis of two decades of research it can be concluded that alley cropping is most likely to work well only on moderately fertile soils without nutrient limitations and when rainfall is adequate during the cropping season (Sanchez, 1995). On sloping land the prospects for contour alley cropping in drier areas are more favourable. In long-term experiments in the semi-arid Machakos area

INTRODUCTION

of Kenya the soil cover of prunings and the Senna siamea hedges themselves greatly reduced erosion, while increased infiltration rates in the soil under the hedges trapped runoff water. This accumulation ofwater under the hedges was such that no competition for soil moisture occurred (Kiepe, 1995). It can be concluded that although in simultaneous associations the interactions between the components ofthe system may be positive, they are often negative. 1.4.2 Aspects of soil fertility One of the most important service functions of auxiliary plants is the maintenance and improvement of soil fertility. Auxiliary plants can fulfil this function by reducing and/or preventing losses from the soil, improving the chemical and physical conditions of the soil and promoting soil biological processes on account ofincreasing inputs (e.g.nitrogen, organic matter). Increasing inputs Through carbon fixation in photosynthesis and its transfer via litter and prunings and subsequent decomposition and via root decay, auxiliary plants can help in maintaining and sometimes in improving soil organic matter levels. It has been estimated (Young, 1989) that to maintain soil organic matter in the humid, sub-humid and semi-arid tropics annual supplies of organic matter in the order of 8 t, 4 t and 2 t dry matter per ha respectively, are needed to compensate for decomposition and minor erosion losses. There is clear experimental evidence that these supply levels can be achieved in cropping systems with auxiliary plants. Some data are given in Table 5. The use of leguminous crops to augment nitrogen in the cropping system is a well-known agricultural practice. Rates ofbiological nitrogen fixation in herbaceous legume crops in fallows and plantation agriculture range annually from a few to 50 kg and up to 200 kg per ha (Giller & Wilson, 1991). Low levels of available phosphate - a common feature of tropical soils - and a lack of soil moisture in drier areas are well-known factors limiting nitrogen fixation. Very few data are available on nitrogen fixation by legume trees and shrubs. Studies on Leucaena leucocephala, however, suggest that shrubs and trees which will yield 50-100 kg biologically fixed N per ha per year in agroforestry systems can be identified. Since most of the nitrogen from leguminous crops is taken up as mineral N from the soil, the N yield ofleaf fall and prunings is at least twice as high (see Table 5). As pruning prevents nutrients being translocated from the leaves to perennial organs (the normal process preceding natural leaf fall) it is an effective practice to ensure that nutrients are re-allocated from the auxiliary crop to the main crop at the proper time (see also 1.5.3). This re-allocation involves the decomposition of residues of natural litter and prunings. The favourable effects of this re-allocation on the nitrogen nutrition of the main crop are well known in rubber. Results presented in Table 6 show that young rubber trees with a leguminous cover return twice as much nitrogen to the soil by annual leaf fall than with a grass ground cover (Watson, 1988). The question of direct N transfer from the roots of auxiliary plants to companion crops is still controversial. Nitrogen-fixing plants in general acidify the rhi-

39

40

AUXILIARY PLANTS

Table 5. Annual return of dry matter and nutrients by auxiliary crops in (kg/ha). Auxiliar}i system

Annual return (kg/ha) dry matter

Prunings ofLeucaena leucocephala hedges planted with a 4 m wide interrow

different cropping systems

7400

Litter and prunings ofErythrina poeppigiana trees at a 6m x 6 m spacing in cocoa plantation 9400

N

P

246

122

K

20

Ca

184

7

27

98

Mg

16

n.a.

n.a

Leguminous cover crops (mixed Calopogonium mucunoides, Centrosema pubescens and Pueraria phaseoloides) in rubber plantation litter only (average annual return during the first two years after establishment)

3019

living biomass and litter at two years after establishment

n.a.

70

283

6

16

25

n.a.

109

10

114

33

n.a. =not available Sources:Alpizar et al. (1986, 1988), Kang &Wilson (1987), Rubber R.I.M. (1972),Watson (1988).

z o s p h e r e a n d t h e r e is evidence t h a t t h i s i n c r e a s e s t h e P u p t a k e from insoluble p h o s p h a t e (see 1.3.3). T h i s would be a n a d d i t i o n a l benefit of g r o w i n g legumin o u s a u x i l i a r y crops (Aguilar S a n t e l i s e s , 1981). U p t a k e of n u t r i e n t s from d e e p e r soil l a y e r s is a n o t h e r m e c h a n i s m by w h i c h deep-rooting a u x i l i a r y crops can i n c r e a s e t h e i n p u t supply. T h e r e is still a lack of q u a n t i t a t i v e d a t a on t h i s . It is clear, however, t h a t a s u b s t a n t i a l i n p u t of n u t r i e n t s can only be expected if subsoils a r e chemically rich, w h i c h is r a r e l y t h e case.

Table 6. Effect of different soil covers on nitrogen cycles and root development ofyoung rubber trees. legume Total annual N return in cover and rubber leaf litter (kg/ha)* Annual N return in rubber leaf litter only (kg/ha)** Rubber roots, surface and 0-8 cm soil layer (kg/ha)*** * averages of4 annual samplings over years 3-5. ** determined over 4 thyear, tree density 408 /ha. *** determined during 3 rd -4 th year. Source: modified after Watson (1988).

grass

240.2

22.4

40.5

19.1

7633

3605

INTRODUCTION

41

Reduction of losses from the soil Auxiliary plants can play an important role in reducing or even preventing carbon and nutrient losses and erosion. Improved fallow crops and cover crops in plantation agriculture intercept and transpire a significant part of the rainfall which would otherwise have caused leaching of nutrients. Deep-rooting auxiliary plants can potentially recover and recycle nutrients leached into deeper soil layers, but the importance of this process is still unknown. The vegetation cover lowers the soil temperature and this slows down the decomposition rates of soil organic matter. Shade trees prevent and reduce losses in a similar way by providing an extra canopy layer. A ground cover of auxiliary plants also reduces nutrient losses in runoff and erosion. Hedges along the contours of slopes have been found to be very effective in erosion control. They check erosion and runoff through the cover effects ofprunings and reduce soil losses through a barrier effect. Moreover, they contribute to the development of terraces through soil accumulation upslope of the hedges. Recent results of a long-term experiment in Kenya confirm earlier findings in Nigeria that contour hedges on sloping land greatly reduce erosion, especially when prunings are applied to the soil surface in the inter-rows (Kiepe, 1995).A summary ofthe Kenyan results is presented in Table 7. Improvement ofphysical soil conditions and biological processes By providing a permanent well-developed living or mulch cover, soils under auxiliary crops exhibit a better structure, porosity and moisture characteristics than most soils under arable crops. The favourable effects ofimproved physical soil conditions on crop growth are well documented and are illustrated in Table 6. Improved soil structure and porosity are linked to the decomposition of plant residues by microorganisms and fauna. Their activity is stimulated by the ex-

Table 7. Mean annual soil loss in t/ha over 6 seasons on a 14% slope at Machakos Research Station, Kenya (Cassia siamea*hedges planted at a distance of4macrosstheslope). Rainfall (mm)

LR** SR** LR SR LR SR

1990 1990 1991 1991 1992 1992

Annual mean

Mean annual soil loss (t/ha) Control

Mulch only

Hedge only

Hedge + Mulch

631 333 214 352 222 808

36.1 0.0 0.0 5.4 3.8 12.6

4.6 0.0 0.0 1.1 0.0 4.1

2.2 0.0 0.0 0.0 0.0 1.6

0.2 0.0 0.0 0.0 0.0 1.2

853

19.3

3.3

1.3

0.5

* Senna siamea ** LR:longrains, SR:short rains Source:Kiepe(1995).

42

AUXILIARY PLANTS

tra supply oflitter and prunings, but depends greatly on the source ofthe plant biomass. Plant residues can be classed as being of high or low quality in terms of decomposition rates. The first category has a low C/N ratio and low lignin and polyphenol contents, and decomposes and releases nutrients rapidly, mainly by microbial and fauna processes. Gliricidia and Leucaena species are among the plants with high-quality residues, hence these residues are a good source of nutrients for fast-growing crops. Low-quality residues with a high C/N ratio and high lignin and polyphenol contents decompose and release nutrients slowly. Mulching with plant residues improves soil conditions by lowering soil temperature and maintaining soil moisture, and slowly decomposing mulches have an advantage for this purpose (Tian, 1992). The foregoing observations imply that auxiliary plants can be specifically chosen for their nutritional effects or as mulch, and that the timing of pruning is important to synchronize soil nutrient supply and crop nutrient demand. 1.5 Management Farmers pay most attention to their primary food and cash crops. They are more interested in production functions than in service functions. Auxiliary plants will therefore probably not receive inputs such as fertilizer, irrigation and pest control. Management is needed in the form of assistance in establishing the plant stand, pruning and harvesting. Therefore, the introduction of auxiliary crops in existing cropping systems is often not attractive, as more labour is involved, and the system becomes more complicated. A green manure that produces an edible by-product is likely to be accepted more readily by farmers. It is likely that in the case of auxiliary crops, the removal of a product will result in depletion of soil fertility if not compensated. Auxiliary crops only increase the ecological sustainability of cropping systems if the emphasis is on their service functions. The production functions, however, can be vital in strengthening the economic basis ofthese systems. 1.5.1 Planting material Most auxiliary species are established from seed. For seeds with very hard impervious testa, as found in many leguminous crops (such as Centrosema pubescens), mechanical or chemical scarification or hot water treatment is used to ensure a quick and even germination. Sometimes seeds are dusted or coated with phosphate fertilizer to improve early growth. Inoculation of seeds with Rhizobium strains to improve nodulation is still in an experimental phase but has given promising results in Brazil with Centrosema macrocarpum Benth. and Pueraria phaseoloides (Sylvester-Bradley & Mosquera, 1985). Some species with poor seed production, for example Vigna hosei, are established from cuttings. Sometimes cuttings are used for economic reasons. Kudzu {Pueraria lobata (Willd.) Ohwi) cuttings, for example, can be planted at 1 m spacing; only the planting spot has to be weeded, as the rapidly growing sprouts quickly overgrow the weeds in the surrounding area. Some woody species like Gliricidia sepium are successfully and cheaply plant-

INTRODUCTION

ed as cuttings. The seedless cross between the varieties glabrata Rose and leucocephala of Leucaena leucocephala is budded on one of the parent rootstocks in Indonesian plantation agriculture, to avoid weed problems caused by profuse seed production. Azolla is propagated vegetatively by means of older secondary stems which detach themselves from the main stem after an abscission layer has been formed. As Azolla cannot stand desiccation, its application depends on the presence of irrigation or perennial ponds. Another condition for its use is the availability and conservation ofinoculum (Cagauan &Pullin, 1994). 1.5.2

Establishment

The growing ofcover crops in admixtures is often practised in oil palm and rubber estates in South-East Asia to quickly achieve a complete soil cover, a gradual phasing out when the canopy closes and to diminish the effects of diseases and pests. A common mixture is Pueraria phaseoloides, a vigorous grower which provides a thick cover and suppresses weeds, Calopogonium mucunoides which shows rapid initial growth but does not persist and is susceptible to pests, and Centrosema pubescens which forms a good cover after a slow initial growth and has some tolerance of shade. Recently, Calopogonium caeruleum (Benth.) Sauv. gained some prominence. In simultaneous systems, planting patterns are important in view of competitive interactions. If crops are mutually non-competitive or beneficial, intimate spatial mixtures can be used. If there is strong mutual competition, auxiliary crops can best be grown in separate blocks or along field boundaries. Alley cropping in which auxiliary plants are arranged in rows or strips represents an intermediate degree of mixing. Distances between hedges depend on the auxiliary species, their possible secondary economic value, and the terrain (slope angle). In most experiments single hedgerows and alley widths of about 4 m have been used, which corresponds with a tree cover of 15-20%. Much greater distances are used for shelter-belts and wind-breaks. During early establishment cover crops have to be weeded, unless they are on newly cleared forest soils. This is one of the reasons that farmers may prefer vigorous and self-seeding fallow crops such as Chromolaena odorata and Sesbania sesban or fast-growing large-seeded species such as velvet bean, rather than the well-known cover crops used in plantation agriculture. 1.5.3 Post-establishment

practices

Once established, plantation cover crops are regularly removed from the tree weeding circles and slashed, especially at the beginning of dry periods, to reduce competition. In rotation systems the cover crops are ploughed into the soil before the next crop is planted. Shade trees are usually planted at a close spacing one or two years ahead of the main crop. Later they are thinned to a final stand, depending on the species and the shade requirements of the crop. Afterwards, shade levels are managed by pruning. Some shade trees such as Erythrina poeppigiana are regularly pollarded or pruned for shade management and the production of mulch. Hedgerow trees and shrubs are periodically pruned to reduce shading and to

43

44

AUXILIARY PLANTS

provide prunings for mulch or fodder. Pruning at the beginning of the cropping season is essential for crop development. Pruning at this time is a major problem for most farmers, however, because it coincides with land preparation and weeding. Both the frequency and the height of pruning affect the biomass production and its N content. An experiment at Ibadan, Nigeria showed that a higher pruning height and less frequent pruning resulted in a higher N yield in a Leucaena hedgerow system, but reduced maize yields due to shading (Duguma et al., 1988). In farming practice a compromise has to be found between mulch production and maize yields. The decomposition rates of prunings depend on the nature of tree and shrub species but also on the mode of application. Leucaena prunings, for example, usually decompose quickly (within 40 days), more rapidly if applied fresh than dried. The direct nutritional effect of prunings is better when they are buried in the soil, because they decompose faster (Young, 1989). Similar results have been obtained with Gliricidia sepium. For practical reasons, surface application is the normal practice. Dried material is easier to transport (less bulky) than fresh material. As to the timing of pruning, additions of organic inputs should be directed at a nutrient release in synchrony with the crop's uptake pattern, not only to promote crop growth but also to reduce losses of released nutrients by leaching and denitrification. The most important cultivation practice with Azolla in rice fields is to incorporate it into the soil. If grown as a sole crop before transplanting, a permanent water layer is needed. If grown as an intercrop, it is incorporated once or several times during the first month after transplanting. Incorporation at a later stage makes nitrogen available during the maturation period. In the intercropping system incorporation is very labour intensive. If Azolla is grown outside the rice field it can continuously produce a biomass which can be incorporated fresh or after composting before transplanting. 1.6 Genetic resources and breeding There is such a diversity of species useful as auxiliary plants that it is complicated to involve institutions to include these genetic resources in their mandate. In addition to the occasional samples in certain botanic gardens, the agricultural research institutes have also gathered germplasm of auxiliary plants. The major international research centres focus on food and technical crops. The International Centre for Research in Agroforestry (ICRAF, Kenya) specializes in agroforestry, and maintains a large database of a multipurpose tree and shrub seed directory (von Carlowitz, 1986). International cooperation in multipurpose tree germplasm is well documented (Burley & von Carlowitz, 1984). The whereabouts of genetic resources of many auxiliary plants can be found in the Food Legumes and Forages volumes of the IBPGR (now IPGRI) Directories of Germplasm Collections (Bettencourt et al., 1992), including most relevant legume species and many browse plants (including legumes too). The various institutions are listed countrywise, and usually more than 80% of the samples are available without restrictions. In the South-East Asian region, the Malaysian Agricultural Research and Development Institute (MARDI) in Serdang, and the Philippine Institute of Plant Breeding (IPB), College of Agriculture in

INTRODUCTION

Laguna are listed as having limited collections of forages. These institutes also have browse legumes in their collections. The Commonwealth Scientific and Industrial Research Organization (CSIRO) of Australia has also accumulated large germplasm collections offorage species with a potential auxiliary role. The Centro Internacional de Agricultura Tropical (CIAT, Colombia) has included South-East Asia in its worldwide search for potential fodder crops, and amongst these several species have auxiliary roles. Although several catalogues are available, they provide few data below the genus level (SchultzeKraft, 1990, 1991a, 1991b). The Kew seed bank at Wakehurst, England, maintains many species for the semi-arid and arid tropics. It provides samples, but in small quantities for research purposes only and in small numbers per species. Unlike many of the food crops, auxiliary species do not have numerous cultivars. Where large amounts of seed are required, it is difficult to obtain the proper ecologically adapted seed source. Information as obtained from the species treatments in this volume points to CIAT and CSIRO as organizations that have the occasional selection of improved fodder crop cultivars, but few particular cultivars have been specially bred for e.g. green manure. An exception is the attention Leucaena has received; many selections of this crop have been released. In several countries with a long-established practice of plantation cropping, such as Malaysia and India, seed of clover and other auxiliary plants can be obtained from commercial companies. 1.7 Prospects Until the 1970s auxiliary crops mainly received attention in plantation agriculture. Suitable species were selected, their service functions and cultivation practices studied and documented, and this resulted in a general adoption in plantation management. Auxiliary crops will continue to play an important role in commercial tree crop cultivation but no major breakthroughs can be expected in this field. During the last 30 years, when degradation of natural resources became an important issue, the need to develop production systems which would integrate growing of trees or shrubs, arable crop production and/or animal husbandry in order to optimize tropical land-use systems became apparent. The study and development of these so-called agroforestry systems has renewed interest in auxiliary crops and put them back on the agenda of international and national research and development organizations. By delivering services and products and by spreading the risk of crop failure, agroforestry systems have the potential to strengthen the ecological and economic basis of agricultural production systems. Ethnobotanical surveys indicate that many multipurpose plants with auxiliary functions are used in traditional agriculture. In the transition from semi-permanent arable cropping to more intensive landuse systems, the role of auxiliary species is likely to increase. However, when the stage of permanent arable cropping is reached, only short-duration fallows with auxiliary crops will be used. Farmers will only adopt this strategy if soil moisture is inadequate for other short-duration crops such as pulse crops. Strip cropping with auxiliary shrubs and woody species has been proposed in permanent arable cropping systems, but multi-locational experiments have clearly

45

46

AUXILIARY PLANTS

shown that these so-called hedgerow intercropping systems are only suitable when soil moisture and soil fertility are not limiting. In some parts of South-East Asia where large areas of wasteland need to be reclaimed for agriculture and forestry, the role of auxiliary plants is becoming very important. Finally, the need to take marginal land into cultivation may also imply an increase in use of auxiliary crops as well. Contour planting with auxiliary trees and shrubs has shown promise, especially on sloping land. Being of less direct importance than the primary crops, research on the role and performance of auxiliary plants has until recently received little attention. Their large potential for fodder and fuelwood production and soil conservation, and their specific, often customized role in traditional cropping systems merits further research. Research on the lesser-known auxiliary plants covered in this volume will prove useful, especially to corroborate the few studies done sofar. The adoption of cropping systems that include auxiliary plants would be facilitated if seed of auxiliary species were more readily available from national and international research centres and from commercial suppliers. M. Wessel &L.J.G. van der Maesen

2 Alphabetical treatment of species

ACACIA

49

A c a c i a a u l a c o c a r p a A. C u n n . e x B e n t h . London Journ. Bot. 1:378 (1842). L E G U M I N O S A E - MlMOSOIDEAE

2n = 26 S y n o n y m s Acacia aulacocarpa A. Cunn. ex Benth. var. macrocarpa Benth. (1864),A. lamprocarpa O. Schwarz (1927), Racosperma aulacocarpum (A. Cunn. ex Benth.) Pedley (1987). Vernacular n a m e s Brown salwood, hickory wattle, New Guinea brown wattle, New Guinea wattle (En). Origin and geographic distribution A. aulacocarpa occurs naturally in Australia, Papua New Guinea and Indonesia. It extends from northern New South Wales, eastern Queensland and the northern parts of the Northern Territory in Australia to southern Papua New Guinea and adjoining areas of south-eastern Irian Jaya. It has been tested in most countries of South and South-East Asia. U s e s The wood of A. aulacocarpa is suitable as firewood, for construction and flooring, boat building, furniture and cabinet work, tool handles, boxes and crates,joinery and turnery. It has excellent potential as a source of fibre for pulping and paper-making industries, producing one of the strongest bleached kraft pulps among acacias. A. aulacocarpa is used in reforestation ofpoor soils. Properties Nutrient content of the foliage per 100 g dry matter is: N 2.2 g, P 0.09 g, K 0.74 g, Ca 0.43 g, S 0.31 g, Mg 0.26 g, Cu 0.9 mg, Zn 4.5 mg, Mn 28.1 mg, Al 8.1 mg, B 3.5 mg. Dry matter digestibility and protein content of the foliage are low, making it unsuitable as a fodder. The weight of 1000 seeds is 12.5-25 g. The sapwood of A. aulacocarpa is narrow, pale yellow to straw-coloured, distinct; heartwood pale olive-brown to grey brown, often attractively streaked with grey bands. The wood is hard, strong, and moderately heavy with a basic density of 600 kg/m 3 , an air-dry density of 645-720 kg/m 3 at 12% moisture content, and an energy value of 21600 kJ/kg. In a test, wood of a 12-year-old tree gave a screened pulp yield of 55.4% with Kappa number 19.3.The sapwood is susceptible to attack by Lyctus borer and the heartwood has low to moderate durability in contact with the ground. Charcoal made from A. aulacocarpa wood has a density of 500 kg/m 3 at 1.25% moisture and an energy value of37 100 kJ/kg. Description Shrub to slender, large tree, 3-40 m tall; trunk up to 1 m in diameter, sometimes fluted. Bark hard, brownish, about 1 cm thick,

Acacia aulacocarpa A. Cunn. ex Benth. 2, flowering branch; 3, pods.

1, habit;

longitudinally fissured, peeling in long strips. Phyllodes straight or falcate, acute or subacute, 5-15 cm x 0.6-3.5 cm, 3-12 times as long as wide, glabrous, greyish-green or dull grey, with 3 prominent longitudinal veins somewhat crowded towards the lower margin at base, usually not yellowish, and with many parallel, not anastomosing, secondary veins; pulvinus 4-6 mm long with an ellipsoid basal gland. Inflorescence a spike, 2-6 cm long, yellow, 1-3 together; peduncle 2-8 mm long, scurfy; flowers 5-merous, bisexual; calyx broadly cupular, 0.5-1 mm long, membranous, with broad, obtuse, scurfy lobes 0.2-0.3 mm long; corolla 1.2-1.9 mm long, lobed to the middle, glabrous, 2-3 times as long as the calyx; stamens many, 2.5-3 mm long; ovary 0.5 mm long, shortly pubescent or scurfy. Pod oblong, up to 10 cm x 2 cm, light brown, coriaceous to subwoody, with prominent obliquely transverse, dark brown veins, glabrous, often twisted when old. Seed elliptical-oblong, 5-8 mm x 2.5-3.5 mm, shiny black, transverse or oblique in pod, with pale terminal aril.

50

AUXILIARY PLANTS

Growth and development Mature seeds germinate readily. After the cotyledons have fully unfolded, a pinnate leaf with 8-10 leaflets emerges. This is followed by a bipinnate leaf. A second bipinnate leaf follows, and usually it is from this leaf position onwards that the flattened petiole expands to form a phyllode, but with a bipinnate leaf remaining intact at the tip. Following this stage, seedlings develop to full phyllode stage, producing phyllodes without intact bipinnate leaves. The adult foliage form is reached about 6 weeks after germination. Trees attain 12-16 m in height and 11-14 cm in diameter in 4 years. A. aulacocarpa was tested in Guyana on strongly leached, white quartz sandy soil with pH 4.7 and an annual rainfall of 2400 mm. It grew to 12.5 m tall in 3 years, whileA. auriculiformis A. Cunn. ex Benth. attained only 7.8 m, and Pinus caribaea Morelet and Paraserianthes falcataria (L.)Nielsen failed completely. A. aulacocarpa is an evergreen atmospheric nitrogen fixing species. The main and lateral shoots grow almost throughout the year, but growth may stagnate during the very hot and dry season. Trees generally start to flower after 3 years. The main period of flowering is from February to April in subtropical Australia and from April to June in tropical parts of its natural range. Insects, especially bees, are believed to be the main pollinating agent. Seeds mature 4-5 months after flowering. It is not uncommon for A. aulacocarpa to produce two seed crops per year. Other botanical information Two varieties have been distinguished: var. aulacocarpa and var. fruticosa C.T. White. The former is a tree, phyllodes with crowded nerves, 7-15 cm long, 4-12 times as long as wide; calyx 0.7-1 mm long; pod usually 1.5-2 cm wide; the latter is a bushy shrub up to 3 m tall, phyllodes with less crowded nerves, 5-10 cm long, 3-5 times as long as wide; calyx 0.5-0.6 mm long; pod 1-1.2 cm wide. Var. fruticosa is restricted to southern Queensland. These and other differences between populations in humid and dry areas are the focus of current taxonomie attention. The most closely related species is A. crassicarpa A. Cunn. ex Benth., whose distribution overlaps that of A. aulacocarpa in northern Queensland and Papua New Guinea. A. crassicarpa has very narrow (2-4 mm), long fruits, whereas A. aulacocarpa has contorted, wider (1-2 cm) ones.A. aulacocarpa is also closely related toA. auriculiformis which has contorted fruits with undulate margins. A. aulacocarpa has phyllodes without anastomos-

ing secondary veins, in A. auriculiformis these veins are somewhat anastomosed. A. aulacocarpa may infrequently hybridize withA. crassicarpa. Ecology The main occurrence ofA. aulacocarpa is in warm to hot humid and sub-humid zones of the tropics and subtropics, at the latitudinal range 6-30°S, and it extends from near sea level in New Guinea up to about 1000 m altitude in Australia. Mean annual rainfall ranges from 500-3000 mm with a monsoonal distribution. The mean minimum temperature ofthe coolest month is 10-21°C and the mean maximum temperature of the hottest month is 29-38°C. A. aulacocarpa is mainly a species of open forest and woodland, but with limited extension into rain forest. In open forest it grows in association with Eucalyptus miniata Cunn. ex Schauer and E. tetrodonta F. v. Mueller, on the edges of semiarid woodland with E. polycarpa F. v. Mueller and E. papuana F. v. Mueller. On rain forest fringes it is often associated with E. pellita F. v. Mueller, E. intermedia R. Baker, Acacia cincinnata F. v. Mueller, A. mangium Willd. and A.polystachya A. Cunn. ex Benth. On the swampy coastal plains of north-eastern Australia and south-western Papua New Guinea, it occurs with A. mangium and A. crassicarpa between wet depressions dominated byMelaleuca spp. A. aulacocarpa grows in a wide topographical range including undulating highlands, ridges, and steep rocky slopes, as well as on the flat and gently undulating terrain of coastal plains and foothills. It is found frequently on yellow earths, red or yellow podzolics that are usually acid or very acid and of low fertility, and on sandy clay soils. It tolerates a wide pH range. Propagation and planting Propagation is generally by seed, although cuttings and air layering can also be used. Seeds have a hard seedcoat which requires heat treatment or nicking to break dormancy. Immersion in boiling water for 1 minute is a suitable treatment. Treated seeds are sown in germination beds and seedlings are transplanted into polythene bags when they reach the 2 leaf-pair stage. Seeds can also be sown directly into polythene bags. Young seedlings should initially be kept at 50% sunlight, but this can be increased to 70% once the seedlings are established. Excess shading often results in attack by mildew and other fungi and damping off. In general, the seedlings are 25-30 cm tall and ready for transplanting 3-4 months after sowing. A spacing of 3-4 m x 3-4 m is considered suitable for firewood and pulpwood plantations.

ACACIA

Husbandry A. aulacocarpa competes very well with weeds including Imperata cylindrica (L.) Raeuschel. In plantations with 2-3 m x 2-3 m spacing, it will totally suppress I. cylindrica grass within 2-3 years. However, weed control is necessary in the first 2years to help establishment. An 8-10-year rotation is recommended for pulpwood plantations, and a 15-20-year rotation for saw logs. A. aulacocarpa does not coppice well, but there is evidence that trees from Queensland respond to coppicing better than those from Papua New Guinea. The coppicing mechanism is not well understood. Diseases and pests Apart from infestation by powdery mildew in the nursery, trees are sometimes attacked by a Sinoxylon sp. that girdles small stems and branches of less than 2 cm in diameter only, causing them to break at the point of attack. Attack by a stem pinhole borer (Lyctus sp.) has been reported in Sabah, Malaysia. Yield A. aulacocarpa has shown considerable variation in growth and yield. In general, provenances from Papua New Guinea grow much faster than those from Australia. At a planting site in southern Thailand, a seedlot from Oriomo, Papua New Guinea, produced an above-ground dry biomass of 103 t/ha in 3 years, twice as much as that produced by material from Queensland. Papua New Guinea provenances have also shown satisfactory growth in Sabah. Genetic resources The Australian Tree Seed Centre, Commonwealth Scientific and Industrial Research Organization (CSIRO, Canberra), has a good coverage ofgenetic material from the natural range in Australia and Papua New Guinea. Seed from Papua New Guinea provenances is also available from the Forest Research Institute in Lae. Seed from seed orchards established in Thailand is now available. Breeding Current breeding programmes are limited to a small number of progeny trials, which are being converted into seed orchards in Australia, Indonesia, Malaysia and Thailand. Prospects Because of its good fuel, timber and pulping characteristics, A. aulacocarpa has great potential as a plantation species in the humid and sub-humid tropics. Its tendency to have a fluted stem may reduce its value for some purposes, like veneer. Its light to moderate shade makes it also useful for shade and ornamental planting. Further study ofthe coppicing mechanism is warranted. Literature 111 Awang, K. & Taylor, D.A., 1993.

51

Acacias for rural, industrial and environmental development. Proceedings of the 2nd meeting of the Consultative Group for Research and Development of Acacias (COGREDA) held at Udorn Thani, Thailand, February 15-18, 1993. Winrock International and Food and Agriculture Organization, Bangkok, Thailand. 258 pp. I2l Clark, N.B., Balodis, V., Fang Guigan & Wang Jinxia, 1991. Pulping properties of tropical acacias. In: Turnbull, J.W. (Editor): Advances in tropical acacia research. Proceedings of an international workshop held in Bangkok, Thailand, 11-15 February, 1991. ACIAR Proceedings No 35. Australian Centre for International Agricultural Research (ACIAR), Canberra, Australia, pp. 138-144. I3lNielsen, I.C., 1992. Mimosaceae (Leguminosae-Mimosoideae). Acacia. In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana. Series 1, Vol. 11. Foundation Flora Malesiana, Leiden, the Netherlands, pp. 34-64. 141 Pedley, L., 1978. A revision of Acacia Mill, in Queensland. Austrobaileya 1(2): 148-149. 151 Sim Boon Liang & Gan, E., 1991. Performance of Acacia species on four sites of Sabah Forest Industries. In: Turnbull, J.W. (Editor): Advances in tropical acacia research. Proceedings of an international workshop held in Bangkok, Thailand, 11-15 February 1991.ACIAR Proceedings No 35.Australian Centre for International Agricultural Research (ACIAR), Canberra, Australia, pp. 159-165. 161 Thomson, L.A.J., 1994. Acacia aulacocarpa, A. cincinnata, A. crassicarpa and A. wetarensis: an annotated bibliography. CSIRO, Division of Forestry, Canberra, Australia. 131 pp. 171 Vercoe, T.K., 1987. Fodder potential of selected Australian tree species. In: Turnbull, J.W. (Editor): Australian acacias for developing countries. Proceedings of an international workshop held at the Forestry Training Centre, Gympie, Queensland, Australia, 4-7 August 1986. ACIAR Proceedings No 16. Australian Centre for International Agricultural Research (ACIAR), Canberra, Australia, pp. 95-100. 181 Visaratana, T., 1991.Coppicing ability of some Australian tree species in Thailand. In: Turnbull, J.W. (Editor): Advances in tropical acacia research. Proceedings of an international workshop held in Bangkok, Thailand, 11-15 February 1991. ACIAR Proceedings No 35. Australian Centre for International Agricultural Research (ACIAR), Canberra, Australia, pp. 43-47. K. Pinyopusarerk

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AUXILIARY PLANTS

A c a c i a a u r i c u l i f o r m i s A. C u n n . e x Benth. London Journ. Bot. 1:377 (1842). L E G U M I N O S A E - MlMOSOIDEAE

2« = 26 Synonyms Racosperma auriculiforme (A. Cunn. ex Benth.) Pedley (1986). Acacia auriculaeformis A. Cunn. ex Benth. is a formerly commonly used orthographic variant ofA. auriculiformis. Vernacular names Northern black wattle (Australian standard trade name), ear-pod wattle, tan wattle (En). Earleaf acacia (Am). Indonesia: akasia, ki hia (Sundanese). Malaysia: akasia kuning. Papua New Guinea: Papua wattle. Philippines: Japanese acacia, auri. Cambodia: smach'té:hs. Thailand: krathin-narong (Bangkok). Origin and geographic distribution Natural stands ofA. auriculiformis are found in Australia (Cape York Peninsula, Queensland, northern areas of the Northern Territory), south-western Papua New Guinea and Indonesia (Irian Jaya, Kai Islands). The domestication of A. auriculiformis began about 50 years ago. It is planted widely in tropical Asia, with extensive plantings in China and India. In western Malesia it has also become naturalized. It is planted to a lesser extent in Africa and South America. Uses A. auriculiformis is a major source of firewood, its dense wood and high energy value contributing to its popularity. It provides very good charcoal which glows well with little smoke and does not spark. In agroforestry systems, A. auriculiformis appears to be used mainly for fuelwood. Its superficial and densely matted root system makes A. auriculiformis suitable for stabilizing eroded land. It has been used widely in revegetation and rehabilitation of degraded land in Indonesia. It is planted to provide shelter along beaches and sea fronts. Because of its tolerance of poor soils it is used in reforestation of tin and bauxite mine tailings. Its phyllodes provide a very good, long-lasting mulch. The wood of A. auriculiformis is extensively used for paper pulp and small saw timber. It makes attractive furniture. Crooked and multiple stems have long restricted its use as poles or other forms of timber that require to be of reasonable length, but genotypes with good trunk form have been identified and are now widely planted. Plantationgrown trees have been found to be very promising for the production of unbleached kraft pulp and high quality neutral sulphite semi-chemical pulp. Large-scale plantations have already been estab-

lished e.g. in Kerala, India, for the production of pulp. The bark is collected locally for use as tanning material. The foliage is not a good fodder and is rarely, if ever, browsed by cattle. Lac insects have been found on trees ofA. auriculiformis in India, but it is probably not a good substitute for traditional host species. An edible mushroom, Tylopylus fellus, is common in plantations ofA. auriculiformis in Thailand. The flowers are a source of pollen for honey producing bees. The dense dark green foliage which remains throughout the dry season makes it an excellent shade tree. It is a popular ornamental tree with attractive, bright yellow flowers. The flowers are marketed in Burma (Myanmar) as altar flowers. Properties Phyllodes decompose slowly in comparison with those of other leguminous trees like Paraserianthes falcataria (L.)Nielsen or Leucaena leucocephala (Lamk) de Wit; this has been attributed to a lower N content and a harder cuticula. In West Java, phyllodes used as a mulch were 95% decomposed after 16 months. The bark contains sufficient tannin (13-25%) for commercial exploitation and contains 6-14% of a natural dye suitable for the soga-batik industry. Leaves have an in vitro dry matter digestibility of 33-37%. Per 100 g dry matter, leaves contain: crude protein 13-16 g, P 0.06-0.11 g, K 0.45-0.72 g, Ca 0.52-0.77 g, Mg 0.18-0.24 g. The wood ofA. auriculiformis contains 66% cellulose, 31% lignin, 16% pentosans and 1.5% ash. Flavonoid substances are present. It is heavy with more than 70% of the volume being heartwood. The sapwood is yellow; the heartwood light brown to dark red, straight grained and reasonably durable. It has a fine to medium texture and is often attractively figured. The density is 490-840 kg/m 3 at 15% moisture content. The fibre is relatively short, about 0.85 mm long and 0.2 |im in diameter. The physical and mechanical properties of the wood as compared to teak as standard are considered high. The wood is easy to work, takes a good polish and finishes well. Boards, however, have a tendency to split when sawn. The energy value ofthe wood is 20 000-20 500 kJ/kg. Tests on A. auriculiformis charcoal carried out in Thailand, gave an energy value of 32 300 kJ/kg and a density of 404 kg/m 3 . It gave little or no smoke or sparks. The weight of 1000 seeds is 15-30 g. Description Tree up to 30 m tall with trunk up to 12 m long and 50 cm in diameter, often smaller with crooked stem and heavily branched; branchlets angular, glabrous. Bark grey or brown, more

ACACIA

53

by a long red or orange funicle; aréole large, almost closed. Growth and development Under favourable conditions, seedlings grow quickly and reach a height of 25-30 cm in 3-4 months, 6 m in 2 years, and 6-12 m in 3 years. Young seedlings produce 2-3 bipinnate leaves, soon followed by phyllodes. Phyllodes are retained during the dry season; their average life is about 1year in West Java. Under favourable conditions, A. auriculiformis grows into a tree, 25-30 m tall, with a straight stem dominant for a greater part of the tree height. Where it is introduced, e.g. in India, it is commonly a low tree, 8-12 m tall, much branched and with a crooked stem. Inbreeding in introduced populations with a narrow genetic base has been suggested as a major cause ofpoor form. Flowering usually starts within 2 years after sowing. Though flowering occurs throughout the year, there is usually a distinct peak flowering season. These periods vary considerably with locality. In Java, for example, peak flowering is from March to June. Seeds mature in 4-5 months and store well. Germination rate is adequate after storage in airtight containers at room temperature for 18 months or for several years in air-conditioned rooms.

Acacia auriculiformis A. Cunn. exBenth. - 1, flowering branch; 2, flower; 3, pods. or less smooth in young trees, becoming rough and fissured with age. Phyllodes curved or falcate, 10-16 cm x 1-3 cm, glabrous, greyish-green, 3-4 longitudinal veins prominent, usually not yellowish, running towards the lower margin or in the middle near the base, with many, fine, crowded, somewhat anastomosing secondary veins; pulvinus 4-6 mm, with at the top a distinct, swollen gland with small rimmed orifice. Inflorescence an axillary, somewhat interrupted spike, 7-10 cm long, growing in pairs; peduncle 5-8 mm long; flowers 5-merous, bisexual, tiny, sessile, goldenyellow, fragrant; calyx tubular, 0.7-1 mm long, shortly lobed, glabrous; corolla 1.7-2 mm long, about 2 times as long as the calyx; stamens many, about 3 mm long; ovary densely pubescent. Fruit a flat pod, about 6.5 cm x 1-2.5 cm, cartilaginous or woody, brown, glaucous, transversely veined with undulate margins, initially straight, on maturity becoming very twisted with irregular spirals. Seed broadly ovate to elliptical, 4-6 mm x 3-4 mm, shiny black, hard, transversely attached, encircled

Nodulation and atmospheric nitrogen fixation by A. auriculiformis are profuse under good growing conditions, but this potential can only be reached where soil fertility, especially in terms of P content, is adequate. In trials in the Philippines, 52-66% of nitrogen uptake has been derived from nitrogen fixation. Nodulation is profuse, with a range of Rhizobium and Bradyrhizobium species. Ecto-mycorrhizal fungi (Thelephora spp.) and endo-mycorrhizal fungi (Glomus etunicatum, Glomus macrocarpum and Gigaspora margarita) have been shown to form effective associations. Other botanical information A. auriculiformis is closely related toA. aulacocarpa A. Cunn. ex Benth. and A. leptocarpa A. Cunn. ex Benth. It is difficult to distinguish from A. aulacocarpa, which has phyllodes with non-anastomosing veins, while those of A. auriculiformis are somewhat anastomosing.A. leptocarpa has long, non-contorted pods with seeds disposed longitudinally, and the veins in the phyllodes are spaced more widely. The natural habitat of A. auriculiformis overlaps with that of several closely related species. Natural hybrids with Acacia mangium Willd. and Acacia leptocarpa occur. The hybrids with A. mangium are intermediate between the two parents in flower, fruit, and seed characteristics and in phys-

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ical and mechanical wood properties. They inherit the better stem straightness of A. mangium and the self-pruning ability and better stem roundness of A. auriculiformis. Their growth is sometimes more vigorous and resistance to heart rot is better. Ecology A. auriculiformis occurs in the humid to sub-humid lowland tropics, growing naturally in narrow strips along river banks but also on coastal dunes, tidal flats, saline lagoons and floodplains. Individual trees may be widely scattered in savanna woodland or swamp forest dominated by tall Melaleuca spp. It occurs naturally from sea level to 400 m. In plantations in Nepal and Zimbabwe it has done well up to 1000 m altitude. In its natural range, the mean maximum temperature ofthe hottest month is 32-38°C and the mean minimum temperature of the coldest month 1220°C. Rainfall varies between 760 mm in the Northern Territory (Australia) and 2000 mm in Papua New Guinea; its distribution is monsoonal and the dry season may last 6 months. Plantations have been established in areas with as little as 650 mm to over 6000 mm rainfall annually. Frost does not occur in its natural range, but elsewhere light frost is tolerated. It does not tolerate shade. Wind tolerance is low, as branches break easily in strong winds. A. auriculiformis is exceptionally tolerant of adverse soil conditions. In Papua New Guinea it grows well on well-drained acid soils and on imperfectly drained heavy clay soils subject to temporary or prolonged waterlogging and flooding. Soils in its natural range in Australia include dune sands, black cracking clays, and alluvium derived from sandstone or latérite. The pH usually ranges from 4.5-6.5, but in the Northern Territory it grows on beach sands with a pH of 8-9, as well as on the spoils of uranium mines with pH 3. It is highly tolerant of soil salinity. In an experiment in Thailand, it continued growing under saline conditions ranging from 0.15 to 7.25 dS/m, in both wet and dry soils. Propagation and planting The use oflocal, often inbred seed sources should be discouraged to avoid inbreeding depression and the resulting poor tree form. Seeds picked at physiological maturity do not show dormancy, but mature seeds require a pregermination treatment, such as immersion in boiling water for 1-2 minutes followed by soaking in cold water overnight or soaking in warm water for 24 hours. After suitable treatment, germination starts about 6 days after sowing and typically exceeds 75%.

Seeds are mostly sown in nurseries. Direct sowing is also possible. Sowing from the air has sometimes been successful, but site preparation prior to sowing is required. Seedlings in the nursery require little attention and there are no serious diseases and pests. Newly emerged seedlings should receive 50% shade; once established, 70% full sunlight is optimal. In general, 3-4 months are needed to raise transplantable seedlings that are 25 cm tall. Inoculation with rhizobia and mycorrhizae is rarely necessary, unless seedlings are raised in sterilized media or planted in highly degraded soils or mine spoils. Methods of vegetative propagation through juvenile cuttings have been developed and are now a routine and simple operation. Trees can be pollarded to produce cuttings. The optimum planting density is not clearly established. Most current plantings employ spacings of 2-4 m x 2-4 m, the closer spacing being more suitable for firewood and pulp plantations. In China, spacings of 1-1.5 m x 1.5-2 m are favoured by farmers producing fuelwood and poles. Husbandry Removal of lower branches of young plants has been suggested as a means of improving stem form and of reducing the incidence of multiple stems. A. auriculiformis responds well to pollarding. Tree age, stump diameter and height are important factors in sprouting, although their effects are not well understood and warrant detailed investigation. Plantings in Imperata grasslands have survived fires, but are generally too severely damaged to make A. auriculiformis a suitable tree for Imperata control. The effect of intercropping with annual crops varies. Increased tree growth has been found with kenaf (Hibiscus cannabinus L.), upland rice and groundnut in Thailand, reduced growth with maize in Cameroon. Diseases and pests No serious diseases and pests occur. Seedlings in the nursery are reported to be infested by powdery mildew and rust, but these do not usually cause serious damage. In nurseries and young plantations in Indonesia growth rates have been impaired by the rust Uromyces digitatus. Root rot caused by Ganoderma lucidum is reported from India. A beetle (Sinoxylon sp.) can girdle young stems and branches, causing them to break. This insect is of concern, because the tree will develop multiple leaders if the main stem is damaged, and the length of the bole will be reduced. Experimental results suggest that A. auriculiformis has some resistance to termites.

ACACIA

Harvesting A. auricuüformis does coppice well, but it does not sprout vigorously or prolifically. Better results are obtained when the stump is cut at a height of 0.6-1 m above the ground. Tree age, stump diameter and season of cutting also influence coppicing ability. It responds well to pollarding. Yield Under favourable conditions, trees may reach a height of 15 m in 5 years, and produce an average annual wood increment of 15-20 m 3 /ha over 10-12 years, the age at which it is usually harvested. On very poor or severely eroded soils, mean annual increment drops to 8-12 m 3 /ha. Under rainfall conditions of 1000-1400 mm/year and a pronounced dry season in West Bengal, India, the mean annual increment was only 2-6 m 3 /ha. Differences between provenances are large. On a well-drained site in Thailand receiving about 1500 mm rainfall annually, a provenance from Balamuk (Papua New Guinea) produced a total aboveground biomass of 135 t/ha in 3 years, while a provenance from Springvale (Australia) reached only 60 t/ha. On a regosol overlaying marl in West Java in a region with a rainfall of 2700 mm/year, the biomass increment from year 3 to 4 was 15.7 t reaching 96.1 m 3 in year 4; stemwood made up 60% of the total above-ground biomass; stem diameter increased from 12.2 cm to 13.6 cm; litter production was 10.7 t/year of which 6.4 t were leaves. Up to 500 g of seed per tree has been collected. Genetic resources The Australian Tree Seed Centre of the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Canberra maintains seed stocks of representative provenances from throughout the natural range of A. auricuüformis. Comprehensive living collections are currently maintained on Melville Island, Australia, and in provenance trials in China, Thailand and elsewhere. Breeding High levels of genetic variation exist in A. auriculiformis. Intra and inter-population genetic variation is considerable and important in initial selections in domestication programmes. Generally, 3 distinct groups can be distinguished, corresponding to their geographic distribution in Queensland, Northern Territory, and Papua New Guinea, respectively. International provenance trials were established in 1989 to examine the extent of genotype x environment interactions. Results from Australia and Thailand show that provenances from Queensland have a higher proportion of straight stems. Several countries have genetic improvement programmes which aim to

55

improve this characteristic. Collection of seeds from phenotypically superior trees, field progeny trials, and seedling-seed orchards have produced promising results. Natural hybridization ofA. auriculiformis with A. leptocarpa and A. mangium has been observed in both natural stands and plantations. Many hybrids show desirable characteristics, such as vigour, fine branching and tendency for strong apical dominance, which will eventually lead to a tree with single stem and a long, straight, branchless bole. Prospects Few species can match the ability of A. auriculiformis to grow on harsh sites in the tropics. Although it grows slower than some other species under optimal conditions, its fast growth rate, the ability to fix atmospheric nitrogen and its tolerance of infertile, acid, alkaline, saline and seasonally waterlogged soils, and of moderately dry seasons make it a most useful tree for the rehabilitation of degraded lands. Its ease of cultivation and multiple uses make it suitable for growing by farmers. Straight-stemmed forms have outstanding prospects for industrial plantations to produce paper pulp and other timber products. The use ofA. auriculiformis as a parent of hybrids is of great potential, perhaps even exceeding the potential ofthe species itself. Literature 111Awang, K. & Taylor, D.A. (Editors), 1992. Tropical acacias in East Africa and the Pacific. Proceedings of a first meeting of the Consultative Group for Research and Development of Acacias (COGREDA) held in Phuket, Thailand, 1-3 June 1992. Winrock International Institute for Agricultural Research, Bangkok, Thailand. 106 pp. 121Carron, L.T. & Aken, K.M. (Editors), 1992. Breeding technologies for tropical acacias. Proceedings of a workshop held in Tawau, Sabah, Malaysia, 1-4 July 1991. ACIAR Proceedings No 37. Australian Centre for International Agricultural Research, Canberra, Australia. 132 pp. 131 Logan, A.F., 1987. Australian acacias for pulpwood. In: Turnbull, J.W. (Editor): Australian acacias for developing countries. Proceedings of an international workshop held in Gympie, Queensland, Australia, 4-7 August 1986.ACIAR Proceedings No 16. Australian Centre for International Agricultural Research, Canberra, Australia, pp. 89-94. 141Nielsen, I.C., 1992. Mimosaceae (Leguminosae - Mimosoideae). Acacia. In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana. Series 1, Vol. 11. Foundation Flora Malesiana, Leiden, the Netherlands, pp. 34-64. l5l Pedley, L., 1978.Arevision of Acacia

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Mill, in Queensland. Austrobaileya 1(2): 172-173. 161 Pinyopusarerk, K., 1990. Acacia auriculiformis: an annotated bibliography. Winrock International Institute for Agricultural Research, Bangkok, Thailand and Australian Centre for International Agricultural Research, Canberra, Australia. 154 pp. 171 Rufeids, C.W., 1987. Quantitative comparison ofAcacia mangium Willd. versus hybrid A. auriculiformis. Forest Research Centre Publication No 40, Sabah, Malaysia. 22 pp. I8l Turnbull, J.W. (Editor), 1991. Advances in tropical acacia research. Proceedings of an international workshop held in Bangkok, Thailand, 11-15 February 1991. ACIAR Proceedings No 35. Australian Centre for International Agricultural Research, Canberra, Australia. 234 pp. I9l Vercoe, T.K., 1989. Fodder value of selected Australian trees and shrubs. In: Boland, D.J. (Editor): Trees for the tropics - growing Australian multipurpose trees and shrubs in developing countries. ACIAR Monograph No 10. Australian Centre for International Agricultural Research, Canberra, Australia, pp. 187-192. llOl Wiersum, K.F. & Ramlan, A., 1982. Cultivation of Acacia auriculiformis on Java, Indonesia. Commonwealth Forestry Review 61: 135-144.

Properties The leaves decompose slowly and are useful as mulch. The sapwood is pale yellowish-brown and heartwood golden-brown. The wood is strong and durable with a density of 670-710 kg/m 3 at 12%moisture content and a basic density of620 kg/m 3 . Its energy value is 22 600 kJ/kg. The weight of 1000 seeds is 20-30 g. Description A small to medium-sized tree, up to 25(-30) m tall; bole often straight and branchless for up to 13-18 m, up to 50 cm in diameter, sometimes fluted at base. Bark dark or greybrown, hard, with deep vertical furrows; inner bark red and fibrous. Phyllodes falcate, 8-27 cm x 1-4.5 cm, 2.5-12 times as long as wide, greyishgreen, glabrous; primary veins 3-5, prominent, yellowish, longitudinal, tending to run into the lower margin at the base; secondary veins parallel, not anastomosing, crowded; pulvinus 4-20 mm long with a circular gland at top. Inflorescence a bright yellow spike, 4-7 cm long, clustered in groups of 2-6 in the upper axils; peduncle 5-10 mm long, rachis thick; flowers 5-merous, bisexual; calyx broadly cupular, 0.5-0.7 mm long, lobes con-

J.W. Turnbull &Kamis Awang

A c a c i a c r a s s i c a r p a A. C u n n . e x B e n t h . London Journ. Bot. 1:379 (1842). L E G U M I N O S A E - MlMOSOIDEAE

2n = 26 Synonyms Racosperma crassicarpum (A. Cunn. ex Benth.) Pedley (1987). Vernacular n a m e s Northern wattle, Papua New Guinea red wattle (En). Origin and geographic distribution A. crassicarpa occurs naturally in north-eastern Queensland, south-western Papua New Guinea and south-eastern Irian Jaya. Experimental plantings have been made in several countries in SouthEast Asia. Uses The wood of A. crassicarpa is suitable for firewood, making charcoal and timber, e.g. for construction, furniture, flooring, board, boat building. It appears suitable for pulping, but more study is required to confirm this use. The tree provides shade and can be planted for weed control and is often cited as an effective species for the rehabilitation of land infested with Imperata cylindrica (L.) Raeuschel. In Papua New Guinea, it is reported to be a very vigorous colonizer of degraded soils following shifting cultivation.

Acacia crassicarpa A. Cunn. ex Benth. - 1, 2, flowering branch; 3, pod.

habit:

ACACIA

cave, lobed to about halfway down; corolla widely spreading, glabrous, 1.3-1.6 mm long, 2-3 times as long as the calyx; stamens 2-3 mm long; ovary shortly pubescent, more densely hairy at the top. Pod woody, ovoid-oblong, flat, 5-8 cm x 2-4 cm, glabrous, dull brown, transversely veined but hardly reticulate. Seed oblongoid, 5-6 mm x 2-3 mm, black, arranged transversely in separate compartments; aréole large and almost closed; funicle folded and thickened, forming a long aril below the seed, pale creamy-yellow. Growth and development Young seedlings first produce pinnate leaves, but develop phyllodes from the 3rd or 4th leaf pair. Under favourable conditions, seedlings grow rapidly reaching 25-30 cm in 3-4 months. A. crassicarpa is one of the fastest growing tropical Acacia spp. It appears to maintain active shoot growth almost the year round, although a few months of stagnation may occur in the dry season. In Sabah, it attained a mean height of 15-23 m and a mean diameter of 10-16 cm in 4 years, outperforming other fast-growing Acacia species including A. auriculiformis A. Cunn. ex Benth. and A. mangium Willd. Assessment at 15months after planting in a progeny/provenance trial in northern Australia showed that the mean height and diameter at breast height of Papua New Guinea provenances were 5.2 m and 5.1 cm respectively. The corresponding averages for Queensland provenances were 3.3 m and 2.9 cm respectively. This faster growth of Papua New Guinea provenances is consistent with results from trials in southern China, southern Queensland and Thailand. In Queensland, A. crassicarpa trees are often small, hardly exceeding 10 m; the typical form is bushy with a heavy crown, although long and straight boles can also be found. Flowering starts as early as 18 months after planting, while seed is produced in abundance after 4 years. Seeds mature 5-6 months after flowering. In its natural range it flowers from June to September and bears mature fruits from October to March. A. crassicarpa is a vigorous atmospheric nitrogen fixer and nodulates well with a group of related Rhizobium strains. Other botanical information A. crassicarpa is sympatric with A. aulacocarpa A. Cunn. ex Benth. to which it is closely related.A. crassicarpa is distinguished by its broader and more woody pods.A. crassicarpa may infrequently form natural hybrids with A. aulacocarpa in northern Queensland (Australia).

Ecology A. crassicarpa occurs mainly in the humid and sub-humid tropics from 8-20°S and from 0-200(-450) m altitude. Annual rainfall in its natural habitat is from as low as 500 mm in Australia to as high as 3500 mm in Papua New Guinea and Irian Jaya. Length ofthe dry season ranges from 6 months at the southern limit of the distribution area near Townsville, Queensland, to 3 months at the northern limit in Papua New Guinea and Irian Jaya. The mean minimum temperature of the coolest month is 15-22°C and the mean maximum temperature of the hottest month is 31-34°C. No frost occurs in its natural range. In Australia, A. crassicarpa is commonly found immediately behind beaches, on the coastal plains and foothills. It appears to be tolerant of salt spray and soil salinity. It occurs on a variety of soil types, from calcareous beach sands, yellow earths derived from granite, red earths on basic volcanic rock to alluvial and colluvial soils derived from a variety of parent material. In Papua New Guinea and Irian Jaya A. crassicarpa is found on the gently undulating terrain of the Oriomo Plateau, on well-drained, strongly acid soils, and also on imperfectly drained soils that flood in the wet season. On former rain forest wetlands with a sandy-loam soil it is superior in growth to Acacia mangium Willd. In the southern coastal lowlands of Queensland A. crassicarpa occurs in the understorey of open forest and in open woodland dominated by Eucalyptus pellita F. v. Mueller, E. tereticornis Smith or E. tessellaris F. v. Mueller. On frontal sand dunes it is found as a windsheared shrub or small tree, 2-8 m tall, behind Casuarina equisetifolia L. and associated with Alphitonia excelsa Reissek ex Endl. On Cape York Peninsula it is associated with Eucalyptus tetrodonta F. v. Mueller,Allocasuarina littoralis L.A.S. Johnson, and Melaleuca spp. In Papua New Guinea, A. crassicarpa occurs frequently with A. aulacocarpa, A. auriculiformis andA. mangium. Propagation and planting Seeds remain viable for many years and heat treatment or nicking of the seedcoat is required to break dormancy. Immersion in boiling water for 1minute is a suitable treatment. Treated seeds are sown in germination beds. Germinated seedlings having 2 pairs of leaves can be transplanted into polythene bags containing a mixture of soil and river sand. Seedlings are raised under partial shade, then in the open, and planted out when stem height reaches 25-30 cm. Inoculation of nursery seedlings with a selected Rhizobium strain prior to

57

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planting out is recommended for maximum nodule development. Vegetative propagation through air layering has given promising results in Thailand. Spacing of 3 m x 3 m (1100 trees/ha) to 4 m x 4 m (625 trees/ha) is suitable for land reclamation, fuelwood and pulpwood plantations. Husbandry On sites dominated by Imperata cylindrica or other weedy plants, weed control is necessary in the first 1-2 years to ensure establishment. Trees do not coppice well. In open situations, the crown is strongly branched and casts a moderate shade. Preliminary observations indicate that A. crassicarpa is resistant to low-intensity fires. Diseases and pests Fungal pathogens of leaves and shoots such as Cercospora sp. can affect productivity, particularly during prolonged periods of high humidity. A. crassicarpa is susceptible to attack by a stemboring beetle (Platypus sp.), in Sabah. The beetle, native to Sabah, bores into the stem and is a vector for fungi and bacteria which weaken and stain the stemwood. Young trees are also attacked by a beetle (Sinoxylon sp.) that girdles small stems and branches ofless than 2 cm in diameter, causing them to break at the point of attack. Yield At Sai Thong in Thailand with 1500 mm mean annual rainfall, A. crassicarpa derived from Woroi Wipim in Papua New Guinea produced a total above-ground dry biomass of 207 t/ha in 3 years, much more than several other species tested. At a poorer site in Ratchaburi in central Thailand it performed as well as other Acacia species tested, producing a total above-ground dry biomass of40 t/ha in 3 years. Genetic resources The Australian Tree Seed Centre, Commonwealth Scientific and Industrial Research Organization (CSIRO), Canberra has a good coverage ofgenetic material from the natural range in Australia and Papua New Guinea. The Papua New Guinea Forest Research Institute in Lae supplies seed of Papua New Guinea provenances. Selected Rhizobium strains are available from the Department ofAgriculture, University of Queensland, Brisbane, Australia. Breeding Current research is limited to a small number of progeny and provenance trials, which are being converted to seedling seed orchards. Prospects Because of its fast growth and its ability to produce large volumes of wood even on infertile land, A. crassicarpa has great potential for various forestry practices. It is also suitable for planting for land reclamation, but is too competitive to grow in combination with annual crops. In-

vestigation into the factors affecting coppicing ability is warranted. Literature 111 Clark, N.B., Balodis, V., Fang Guigan & Wang Jinxia, 1991. Pulping properties oftropical acacias. In: Turnbull, J.W. (Editor): Advances in tropical acacia research. Proceedings of an international workshop held in Bangkok, Thailand, 11-15 February 1991. ACIAR Proceedings No 35. Australian Centre for International Agricultural Research (ACIAR), Canberra, Australia, pp. 138-144. 121Harwood, C E . , Haines, M.W. & Williams, E.R., 1993. Early growth ofAcacia crassicarpa in a seedling seed orchard at Melville Island, Australia. FAO Forest Genetic Information 21: 46-53. 13! Nielsen, I.C., 1992. Mimosaceae (Leguminosae - Mimosoideae). Acacia. In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana. Series 1, Vol. 11. Foundation Flora Malesiana, Leiden, the Netherlands, pp. 34-64. l4l Pedley, L., 1978.A revision of Acacia Mill, in Queensland. Austrobaileya 1(2): 147-148. 151 Sim Boon Liang & Gan, E., 1988. Comparative growth of 5 tropical acacias on four different sites in Sabah. Commonwealth Forestry Review 67: 149-158. 161 Skelton, D.J. & Howcroft, N.H.S., 1987. Seed production and silvicultural trials of acacias in Papua New Guinea. In: Turnbull, J.W. (Editor): Australian acacias for developing countries. Proceedings of an international workshop, Gympie, Queensland, Australia, 4-7 August 1986. ACIAR Proceedings No 16. Australian Centre for International Agricultural Research, Canberra, Australia, pp. 188-190. 171 Thomson, L.A.J., 1994. Acacia aulacocarpa, A. cincinnata, A. crassicarpa and A. wetarensis: an annotated bibliography. CSIRO Division of Forestry, Canberra, Australia. 131 pp. I8l Turnbull, J.W., 1986. Multipurpose Australian trees and shrubs: lesser known species for fuelwood and agroforestry. ACIAR Monograph No 1. Australian Centre for International Agricultural Research, Canberra, Australia, pp. 128-129. K. Pinyopusarerk &C.E. Harwood

Acacia glauca (L.) Moench Methodus: 446 (1794). LEGUMINOSAE - MIMOSOIDEAE

2« = 26 Synonyms Mimosa glauca L. (1753),Acacia villosa (Swartz) Willd. (1806), including forma glabra Backer (1963), Acaciella villosa (Swartz) Britton &Rose (1928).

ACACIA

Vernacular n a m e s Wild dividivi, redwood, wata pana (En). Acacia (Am). Amourette (Fr). Indonesia: mlanding sabrang, mlanding merah (Java), petes merah (West Timor). Origin and geographic distribution A. glauca originated in tropical America. It is common in parts of southern Central America and on many West Indian islands, in particular on Curaçao and Barbados. In 1920, A. glauca was introduced into Java, where it then naturalized, especially in the region of Yogyakarta. It has been planted experimentally in the Philippines, where it is said to have naturalized as well. Uses In Indonesia A. glauca was originally planted as an alternative undershrub to Leucaena leucocephala (Lamk) de Wit in teak plantations. At present, it is mainly used to rehabilitate degraded and denuded lands and as a stabilizer of terrace ridges. It is a common ornamental throughout the tropics. The wood is suitable for fuel and for making household tools.A. glauca has been used as a host plant for the lac insect Laccifer lacca in East Java. In West Timor it is used as a forage, but it is generally reported for Java that goats and other livestock do not like it, although chicken eat the seeds. In the Caribbean an infusion ofthe roots or leaves in vinegar and of the bark in water is used as a gargle to relieve sore throat and alleviate oral inflammations. A decoction of peeled branches with vinegar and sugar is taken as a cough medicine. Properties An analysis of dried leaves from Indonesian material gave per 100 g: crude protein 27 g, ether extract 4.8 g, non-digestible fibre 24 g, total phenolics 12.6 g, tannins 6 g. Weight of 1000 seeds is 11g. Botany Erect, unarmed shrub or small tree, l-3(-5) m tall, with open crown and many dark red stems and branches. Root system tough and spreading, superficial. Branches terete, sparsely pubescent to glabrous, younger twigs more strigose. Leaves bipinnately (sometimes tripinnately) compound, pinnae in 2-10 pairs, 4-9 cm long, rachis 8-12 cm long, glandless; leaflets 10-30 pairs per pinna, opposite, oblong-lanceolate, 4-10 mm x 1-2 mm, unequal sided, base rounded, top blunt with acute tip, hairy to glabrescent; stipules lanceolate, early caducous. Inflorescence a short, sometimes subcapitate, 20-40-flowered spike, 2-6 together in the upper axils, the uppermost arranged in racemes; peduncle up to 2.5 cm long, pedicel 1-2 mm, articulated; flowers 5-merous, bisexual, white turning yellow-

Acacia glauca (L.J Moench - 1, flowering branch; 2,pod; 3, seed. ish; calyx campanulate, 0.5-1 mm long, 5-lobed; corolla tubular, 5-lobed, 2-4 mm long; stamens numerous, ovary stipitate with 5 mm long style. Fruit a flat, membranaceous pod, oblong to strapshaped, 1.5-10 cm x 0.5-2 cm, stalk about 1 cm long, apiculate, glossy brown, 1-8-seeded, valves swollen where seeds develop, transversely veined along the margins. Seed ovoid to lenticular, brown. A. glauca extends itself by root suckers from its comparatively superficial root system. In experiments in Indonesia comparing its performance with other fast-growing legumes, A. glauca was consistently among the fastest growing species, especially on very poor soils. It can reach a height of about 3 m and a stem diameter of 3 cm in 13 months from planting. Growth during the juvenile phase is often stronger than in Leucaena leucocephala; after 6 months, however, it loses its advantage. Flowering and fruiting may start very early; in an experiment in Indonesia flowering started within 6 months from planting. It flowers throughout the year.

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The habit ofA.glauca is quite similar to the shrub forms of Leucaena leucocephala, but young twigs are more reddish and pods shorter and more rounded. The synonymous name Acacia villosa is still very commonly used in South-East Asia. In 1753, Linnaeus described this species as Mimosa glauca. Later, however, he used this name for a species that is now known as Leucaena leucocephala, causing much confusion. Ecology A. glauca prefers a rather dry climate. It even grows well where mean annual rainfall is as low as 200-500 mm and the relative humidity 55-70%. In Indonesia, optimum rainfall is about 1200 mm/year in regions up to 1200 m altitude. It performs poorly under low temperature and does not tolerate frost. A. glauca occurs in secondary vegetation, especially on limestone, but also on non-calcareous soils. On very poor soils it will grow better than L. leucocephala and most other legume species. It is less tolerant of shade than L. leucocephala, but reports ofits tolerance ofwaterlogging are contradictory. Agronomy Propagation is by seed or by root suckers. Germination is irregular, unless seeds are scarified or treated with hot water. In the West Indies A. glauca spreads very easily and is never planted. Nevertheless, it has not become a noxious weed in Indonesia. A. glauca tolerates heavy pruning and produces root suckers regularly. In comparison with L. leucocephala, it has a more superficial root system and produces fewer leaves. A. glauca is generally free ofdiseases and pests. Genetic resources and breeding It is unlikely that any substantial germplasm collections are being maintained and there are no known breeding programmes. Prospects Observations over many years and experimental results in Indonesia and the Philippines indicate that A. glauca is a very useful undershrub in forest plantations, a shrub legume in agroforestry and a species to rehabilitate degraded soils. In view of its good performance on very poor soils and its unpalatibility to livestock, its use as an alternative toLeucaena leucocephala deserves wider attention. Literature 111 Danimihardja, S., Saefudin, Syarif, F. & Setyowati-Indarto, N., 1988. Pertumbuhan beberapa jenis Leguminosa tumbuh cepat di lapangan setelah semainya diinokulasi dengan Rhizobium [The growth of some fast-growing legume species in the field after seedling inoculation with Rhizobium]. Berita Biologi 3(8):

377-381. 121 de Wit, H.C.D., 1961. Typification and correct names of Acacia villosa Willd. and Leucaena glauca (L.) Bth. Taxon 10: 50-54. 131 Dirdjosoemarto, S., 1981. The performance of some small tree legumes on eroded lands at Wanagama experimental forest. In: Wiersum, K.F. (Editor): Observations on agroforestry on Java. Gadjah Mada University, Yogyakarta, Indonesia and Agricultural University, Wageningen, the Netherlands, pp. 90-96. I4lNielsen, I.C., 1992. Mimosaceae (Leguminosae - Mimosoideae). Acacia. In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana. Series 1, Vol. 11. Foundation Flora Malesiana, Leiden, the Netherlands, pp. 34-64, 208. I5l Riyanto, T.W., 1979. Perbandingan pertumbuhan lamtoro dan mlanding sabrang pada beberapa kondisi tanah [Comparison between the growth of Leucaena leucocephala and Acacia villosa under different soil conditions]. Duta Rimba 5(33): 3-6. I6l Rudjiman, 1981. Multiple-purpose species for planting on critical soils on Java. In: Wiersum, K.F. (Editor): Observations on agroforestry on Java. Gadjah Mada University, Yogyakarta, Indonesia and Agricultural University, Wageningen, the Netherlands, pp. 81-83. 171 Serrano, R.C., 1988. Alternatives to ipil-ipil for agroforestry. Philippine Council for Agriculture, Forestry and Natural Resources Research & Development (PCARRD) Monitor 16(3): 1, 10. J. Jukema &S. Danimihardja

A e s c h y n o m e n e afraspera J. L é o n a r d Bull. Jard. Bot. Etat Brux. 24:64 (1954). LEGUMINOSAE - PAPILIONOIDEAE

2re =80 Synonyms Aeschynomene aspera auct., non L., Sesbania leptocarpa auct., non DC. Vernacular n a m e s Sola pith (En). Thailand: sano (refers to related species as well). Origin and geographic distribution A. afraspera is believed to have originated in sub-Saharan Africa between Senegal and Sudan. It is widely distributed in the lowlands of western, central, north-eastern and southern Africa. In 1986 it was introduced into the Philippines and since then has been grown experimentally across South and South-East Asia. Uses The potential use ofA. afraspera as a fastgrowing nitrogen source for wet-rice fields has only recently been noted. Since the late 1980s it has been widely used as a pre-rice green manure crop

AESCHYNOMENE

on experimental stations and in extension demonstration trials. So far it is only occasionally used by farmers in South and South-East Asia. In its region of origin A. afraspera is grazed by ruminants. In Zambia it is valued as a palatable forage legume. In Senegal the pith of the stems is used as insulation material and medicinally it is applied to stop bleeding. Properties The fresh biomass of young A. afraspera contains 10-20% dry matter and has a C:N ratio of 10-16. Per 100 g dry material the above-ground parts contain: N 2.5-3.7 g, P 0.280.55 g, K 1.3-2.3 g, lignin 9-13 g. As a green manure A. afraspera mineralizes rapidly. The weight of 1000 seeds is 21-29 g. Description Erect to suberect, branching, herbaceous, annual shrub, 1-3 m tall. Root and stem hollow or pith-filled. Stem glabrous, soft, with abundant, spirally arranged, white or pale green adventitious root primordia, which may develop into hemispherical, green nodules. Leaves alternate, composite, stipulate, sensitive; petiole

Aeschynomene afraspera J. Léonard - 1, flowering and fruiting stem part; 2, base of stem with roots and nodules.

61

and rachis 3-18 cm long, 1.5-3 cm in short, axillary branchlets; leaflets (20-)50-100, linear-oblong, 8-20 mm x 1.5-3 mm, 4-7 mm long in leaves on axillary branches, entire or finely denticulate, glabrous. Inflorescence an axillary raceme, 2-6 cm long with 1-6 flowers; bracts glabrous, 3-8 mm x 2-5 mm; pedicel 5-9 mm long (in fruit up to 12 mm), pubescent; calyx bilabiate, glabrous or slightly pubescent on the outside, 6-8 mm long and 4-4.5 mm wide; corolla pale to bright yellow; standard elliptical to obovate, 9-12 mm x 7-10 mm; wings free, 7 mm x 2 mm; keel petals pubescent, about elliptical, loosely adnate, 9-11 mm x 3-4 mm. Pod 5-8 cm x 7-8 mm, venose when young, very warty and dark brown to black when mature, with 6-10 1-seeded segments. Growth and development Initial growth until 5-leaf stage is slow. With the onset of stem nodulation and/or closure of the canopy A. afraspera grows rapidly, reaching 0.6-1.5 m in 2 months. Plants growing in isolation are sub-erect to spreading, with abundant branching. In a dense stand, plants grow erect with a single stem. Under flooded conditions, a shallow taproot with abundant intervascular aerenchyma develops and root primordia grow into adventitious roots. In the Philippines A. afraspera starts flowering 65 days after sowing during the short-day season, and after 80 days when daylength exceeds 12 hours. With prolonged soil flooding, the otherwise short flowering period can extend to over 2 months. Fruit ripening causes drying and brown discolouration of leaves and stems, ending the growth cycle. The most distinctive characteristic ofA. afraspera is the presence ofnitrogen-fixing nodules, not only on the roots but also on predetermined, sub-epidermal primordia of adventitious roots on stems and branches. Upon infection with rhizobia via rain splash or insect activity the root primordia can develop into nitrogen-fixing nodules. Since root nodules are scarce under anaerobic conditions in flooded soils, A. afraspera has to rely on stem nodules to fix atmospheric nitrogen. Root primordia on stems become visible in 2-week-old plants, and profuse stem nodulation is apparent 3-5 weeks after germination. Up to 400 nodules can be found on the stem of a 2-month-old plant and 70-80% of the nitrogen in the biomass is reportedly derived from biological nitrogen fixation, indicating the high efficiency of the symbiosis in stem nodules. Though the roots ofA. afraspera are nodulated by several rhizobium strains, the rhizobia nodulating both roots and stems seem to be

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highly host-specific. Strain ORS 322, isolated from a stem nodule of A. afraspera at the Office de la Recherche Scientifique et Technique d'Outre-Mer (ORSTOM) in Senegal, effectively nodulates only A. afraspera and A. nilotica Taub. It is believed to belong to the genus Bradyrhizobium, but also seems closely related to purple photosynthetic bacteria (Rhodospirilliaceae) as it forms bacteriochlorophyll 'a' and is capable of photosynthesis. The new generic name Photorhizobium has been proposed. Preliminary observations indicate that the nitrogen-fixation rate of stem nodules is less reduced by available soil nitrogen than is the case in root nodules. Other botanical information In the past A. afraspera (strictly African) has been confused with A. aspera L. from tropical Asia. A. aspera is often glandular-pubescent, the calyx is 7-10 mm x 5-6 mm, the standard 10-16 mm x 8-15 mm, the wings 7-12 mm x 4-5 mm and the fruit segments bear spiny warts. At least 18 species of the genus Aeschynomene L. have been shown to produce stem nodules, including the Asian species A. indica L. In most species stem nodulation is less profuse than inA. afraspera. Ecology A. afraspera is found from 0-900 m altitude in tropical areas with a distinct dry season and a monomodal rainfall distribution. It is a semi-aquatic pioneer plant of marshes and temporarily wet places. Seeds require high soil moisture or flooded conditions for germination, but more than 2 cm of standing water prevents seedling growth. It can form dense stands in soil depressions that are waterlogged during the rainy season, and in coastal freshwater lakes and rivers. It occasionally appears as a weed in rice fields. Provided with sufficient plant-available phosphorus (at least 10 ppm Olsen P), A. afraspera will grow in a wide range of soils, from pure dune sands along rivers to peat soils in mangrove swamps. Soil reaction can range from alkaline in salt flats to highly acidic in acid sulphate soils. Propagation a n d planting Dormancy and an extremely hard seedcoat prevent easy germination. For agronomic use, seeds need to be mechanically scarified or immersed for 30-60 minutes in concentrated sulphuric acid. Vegetative propagation is possible using stem cuttings with root primordia. Cuttings 15-20 cm long from the basal stem show the highest survival rate and best growth. Vegetative propagation may not be economic for green manure purposes, and is mostly used to establish seed production plants, e.g. along the bunds ofwet-rice fields.

Planting can be done throughout the year: e.g. at the International Rice Research Institute, Los Banos, the Philippines, planting date had little effect on yield and a limited effect only on the rate of atmospheric nitrogen fixation. Husbandry The ability ofA. afraspera to form above-ground nodules and to fix nitrogen in waterlogged and marginal soils largely determines its value as a green manure in wet rice. Due to its soft structure,A. afraspera green manure is easily incorporated into the soil and mineralizes rapidly even under flooded conditions. After 6-8 weeks of growth it is ploughed in and rice is transplanted 1-7 days later. In eastern India it is sometimes sown as an intercrop between rows of rice and trampled into the soil before it starts shading the rice. Relay planting ofA. afraspera has been used successfully to exploit the short fallow period between two rice crops in multiple cropping systems. Diseases and pests Few diseases and pests are reported. This may be related to the limited use of A. afraspera in agriculture so far. A bacterial wilt is reported to affect biomass production in some areas. The leaf-eating larvae of the Lepidopterous species Eurema lecabe can become a problem when A. afraspera is grown in the short-day season. Stunted growth ofupland A. afraspera may in some cases be associated with cyst-forming nematodes. However, under favourable wet conditions, A. afraspera seems to largely outgrow disease and pest-related damage. When grown for longer than 75 days A. afraspera can effectively control the rice root nematode Hirschmanniella oryzae. Yield An 8-week-old crop grown in a pure stand can accumulate a dry biomass of 4-6 t/ha with a corresponding N yield of 80-200 kg/ha, provided sufficient water and soil P are available; 70% or more of this may be the result of biological nitrogen-fixation. As an intercrop, 35-60 kg N/ha can be accumulated. A rice crop following A. afraspera may recover 90% of the nitrogen contained in the green manure, compared with a recovery rate of 60% from urea. Reported increases in rice grain yield due to the incorporation of a 6-8-week-old A. afraspera green manure range from 0.8-3.2 t/ha. Genetic resources and breeding The biofertilizer germplasm collection at the International Rice Research Institute, Los Banos, the Philippines, maintains 45Aeschynomene species, including 3 accessions ofA. afraspera. Other collections of Aeschynomene are maintained at the Office de la Recherche Scientifique et Technique d'OutreMer in Dakar (Senegal), and at Tamil Nadu Agricultural University (TNAU) in Coimbatore, India.

ALBIZIA

No breeding programmes are known to exist. Prospects Flood tolerance, rapid growth, high nitrogen-fixing activity and rapid decomposition and mineralization giveA. afraspera a high potential as a short-duration green manure in wet-rice systems. Growing concern for agricultural sustainability coupled with the rising cost of mineral N fertilizer mean that it may become more important in South and South-East Asia. Its high nitrogen content and good palatability make it a promising forage crop as well. Literature 111 Alazard, D., 1985. Stem and root nodulation in Aeschynomene spp. Applied and Environmental Microbiology 50: 732-734. 121Alazard, D. & Becker, M., 1987. Aeschynomene as green manure for rice. Plant and Soil 101: 1 4 1 143. 131 Becker, M., 1990. Potential use of the stem-nodulating legumes Sesbania rostrata and Aeschynomene afraspera as green manure for lowland rice (Oryza sativa L.). PhD Thesis, Justus Liebig University, Giessen, Germany. 113 pp. |4| Berhaut, J., 1979. Flore illustrée du Sénégal [Illustrated flora of Senegal], Vol. 5, Editions Clairafrique, Dakar, Senegal, pp. 26-27. 151 Ladha, J.K., Pareek, R.P. & Becker, M., 1992. Stem nodulating legume-Rhizobium symbiosis and its use in lowland rice. Advances in Soil Science 20: 147-192. 161 Watanabe, I., Roger, P.A., Ladha, J.K. & Van Hove, C , 1992. Biofertilizer germplasm collection at IRRI. The International Rice Research Institute, Manila, the Philippines. 66 pp. M. Becker

Albizia c h i n e n s i s (Osbeck) Merrill Amer. Journ. Bot. 3:575 (1916) {Albizzia chinensis). L E G U M I N O S A E - MlMOSOIDEAE

2re = 26 Synonyms Mimosa chinensis Osbeck (1757), Albizia stipulata (DC.) Boivin (1838),A. marginato(Lamk) Merrill (1910). Vernacular n a m e s Silk tree (En). Chinese albizia (Am). Indonesia:jeungjing (Sundanese), sengon (Javanese), keura (Eastern Sumba). Cambodia: kôôl. Laos: kha:ng (Xieng Khouang), kha:ng hu: (Vientiane). Thailand: kang luang, san-kham (Northern), khang hung (Khon Kaen). Vietnam: s[oos]ng r[aws]n t[af]u, cham (Ha Tuyên), chu m[efj (Quang Ninh). Origin and geographic distribution A. chinensis occurs naturally in India, Burma (Myan-

mar), Thailand, Indo-China, southern China, Java and the Lesser Sunda Islands (Bali and Nusa Tenggara). In Borneo and Sumatra, it is possibly only found in cultivation. It is cultivated in many tropical countries. Uses A. chinensis is commonly used as a shade tree in tea and coffee plantations, often in a mixture with other trees like Paraserianthes falcataria (L.) Nielsen and Erythrina spp. In China shade-tolerant herbs are sometimes planted under A. chinensis. It is planted for slope stabilization and soil improvement. In parks and gardens and along roads it is grown as an ornamental. The tree has shown some potential as a fodder: the leaves are readily eaten by goats but the bark of branchlets is hardly touched, possibly because of its high saponin content. Due to the light weight of its wood, timber use is limited to house building, light furniture, tea chests and veneers. In India, it is used in boat building. As a firewood it is oflow quality. Properties Foliage ofA. chinensis contains per 100 g dry matter: crude protein 21-28 g, fat 5 g, neutral detergent fibre 35-60 g, acid detergent fibre 25-35 g, lignin 15 g, tannins 23-33 g, and ash 5-15 g. In rumen degradation tests, digestibility of freeze-dried leaf dry matter was 39% after 48 hours, nitrogen digestibility was 27%. Drying leaves at 60°C in a forced-draught oven decreased total tannin content and increased N digestibility to 45%,while dry matter digestibility decreased to 30%. The bark ofA. chinensis contains triterpenes with spermicidal activity. The trunk of the tree contains gum of low quality. It has been mixed with other gums to be used as extender. Weight of 1000 seeds is about 20 g. The wood of A. chinensis is soft and not very durable. Sapwood is white, while heartwood is light to dark brown. It is resistant to the European subterranean termite (Reticulitermes lucifugus) and somewhat resistant to attacks by Cryptotermes and other insects. An extract ofthe wood has a repellent property to subterranean termites. Description Unarmed, deciduous or evergreen tree with flat, spreading crown, up to 30(-43) m tall and trunk up to 70(-140) cm in diameter; bark dark grey, rather smooth, densely hooped, lenticellate, thin; live bark 5 mm thick, pinkish-red. Branchlets slightly angular in the distal parts, terete, puberulous to tomentose, glabrescent. Leaves bipinnate; stipules auriculate, very prominent, 1-1.5 cm x 0.6-3 cm, caducous, pinkish-orange, pubescent, with filiform tail, base much dilated at one side; rachis stout, 10-25 cm long,

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Albizia chinensis (Osbeck) Merrill - 1, habit; 2, leafy branch; 3, central flower; 4, marginal flower; 5, pod. lenticellate, sparsely and minutely tomentellous, glabrescent, with an elliptical, raised gland near the base of 2-3 mm x 1-1.5 mm; pinnae 4-14(-20) pairs, 4-14 cm long, puberulous to tomentose, glabrescent, with glands at the junctions of the 1 or 2 distal pairs of leaflets, narrowly elliptical to slit-like, concave, 1 mm long, glands sometimes absent; leaflets (10-)20-30(-45) pairs per pinna, opposite, sessile, thinly chartaceous, asymmetrically subulate, 6-10 mm x 1.5-3.0 mm, apex sharply acute, base obtuse, oblique, midrib close to the upper margin, sparsely sericeous or glabrous on either side. Inflorescence consisting of pedunculate glomerules (heads) aggregated into terminal, yellowish-green, tomentose to hirsute panicle; peduncle 1-3 cm long, up to 5 in clusters, often with auriculate stipules at base; glomerule composed of 10-20 flowers; flowers pentamerous, dimorphic; in a glomerule the central flower is male, the marginal flowers are bisexual; calyx tubular to narrowly funnel-shaped, 2.5-5.0 mm long, tomentose to hirsute, ending in small trian-

gular teeth; corolla funnel-shaped, 6-10 mm long, puberulous to hirsute especially on the lobes, lobes triangular-ovate, acute; stamens numerous, 2 cm long, at the base united into a tube as long as or slightly longer than the corolla tube; ovary glabrous, sessile. Pod thin, flat, strap-shaped, 6-20 cm x 2-3 cm, often with slightly sinuate margins, indéhiscent or breaking irregularly, reddish or yellowish-brown, glossy, 8-12-seeded. Seed flattened ellipsoid, 7(-10) mm x 4-6 mm x 0.5-1 mm, dull dark brown, aréole nearly circular, 1 mm in diameter. Seedling with epigeal germination. Growth and development A. chinensis is evergreen or leafless for a short period. In SouthEast Asia trees flower between September and June, fruits ripen between October and August. In northern India old leaves fall in January-February, new ones appear in March-April; flowering takes place soon after the appearance of the leaves; while pods attain full size by about September and ripen during December-March. The pods remain on the tree for a very long time and eventually dehisce, but are sometimes blown away by the wind before dehiscence. Without seed treatment the germination rate is only 5-7%. Growth is very rapid, to 1.5 m within the year of planting. In natural forest an annual diameter increment of2.7 cm has been recorded. Nodulation is abundant and effective, and the nodules, which are dichotomously branched, grow throughout the year. Other botanical information Philippine specimens, formerly referred to this species, have been referred to Albizia philippinensis Nielsen. They differ from A. chinensis in having smaller stipules, petiolar glands and flowers, and seeds with a larger aréole. The related American species Albizia carbonaria Britton (synonym Albizia sumatrana v. Steenis) is also occasionally used as a shade tree in tea in Java and Sumatra. Ecology A. chinensis is a native of mixed deciduous forest and rain forest in humid tropical and subtropical monsoon climates with annual rainfall varying from 1000-5000 mm. It occurs in secondary forest, along river banks, and in savannas up to 1800 m altitude. Light frost is tolerated. It is adapted to poor soils, high pH, is fairly salt-tolerant and thrives on lateritic alluvial soil and sandy mining areas. In growth trials on poorly drained, infertile, gleyed, podzolic soils it had a survival rate ofnearly 100%. Propagation and planting A. chinensis is mostly propagated by seed. Dormancy can be broken by scarification or soaking seed in concentrât-

ALBIZIA

ed sulphuric acid for 10 minutes, followed by washing and soaking in water for 18 hours. After 6-8 weeks, the seedlings can be transplanted into the field. In tea plantations in India A. chinensis is planted at a spacing of about 7-15 m; for fodder production, the trees are grown at a spacing of 3 m x 1 m. At planting a small amount of a mixture of 60% lime, 30% superphosphate and 10% urea is mixed with the soil in each planting hole, to promote early growth. Husbandry Weeds have to be controlled regularly after transplanting until the plants reach a height of 1 m. Trees grown for shade are left to grow to about 7 m tall and are then cut back to 4 m. The trees can be harvested for fodder twice a year during the growing season by cutting the stem back to 1m. Such cutting is well tolerated. Diseases and pests No serious diseases have been reported, though the risk of canker reduces the life expectancy in north-eastern India to about 20 years. Attacks by thrips sometimes prevent flower opening and young pods can be damaged by beetles and larvae ofvarious bruchids. Yield In trials in south-eastern Queensland, with 1500 mm annual rainfall, the mean annual leaf dry matter yield was 454 g per tree with stem dry matter yield of 584 g per tree. In north-eastern Thailand with 1200 mm rainfall, annual yield per tree was 360 g leaf dry matter and 480 g stem dry matter. Genetic resources and breeding It is unlikely that substantial germplasm collections exist and there are no known breeding programmes. Prospects As a fast growing tree legume, A. chinensis remains important as a shade tree especially in tea and in the reforestation of degraded land. Because of its tolerance of frequent pruning during the growing season it deserves testing in alley cropping systems. The tree has shown some value as a source of fodder, warranting further testing. Breeding and selection for low tannin content may result in higher dry matter and nitrogen digestibility. Literature 111Ahn, J.H., Robertson, B.M., Elliot, R., Gutteridge, R.C. & Ford, C.W., 1989. Quality assessment of tropical browse legumes: tannin content and protein degradation. Animal Feed Science and Technology 27: 147-156. 121 Akkaseng, R., Gutteridge, R.C. & Wanapat, M., 1989. Evaluation of trees and shrubs for forage and fuelwood in Northeast Thailand. The International Tree Crops Journal 5: 209-220. I3l Dutta, A.C., 1977. Shade trees, green crop and cover

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plants in the tea estates of North East India. Memorandum 30, Tea Research Association, Tocklai Experimental Station, Jorhat, Assam, India, pp. 8-9. 141Nielsen, I.C., 1992. Mimosaceae (Leguminosae - Mimosoideae). Albizia. In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana. Series 1, Vol. 11. Foundation Flora Malesiana, Leiden, the Netherlands, pp. 64-86, 212. 151 Shelton, H.M., Lowry, J.B., Gutteridge, R.C. & Bray, R.A., 1991. Sustaining productive pastures in the tropics. 7. Tree and shrub legumes in pastures. Tropical Grasslands 25: 119-128. I6l Supriana, N., 1989. Studies on the natural durability oftropical timbers to termite attack. International Biodeterioration 24: 337-341. R.Akkasaeng &R.C. Gutteridge

Albizia p r o c e r a (Roxb.) B e n t h . London Journ. Bot. 3:89 (1844). LEGUMINOSAE - MIMOSOIDEAE

2n = 26 Synonyms Mimosa procera Roxb. (1799), Acacia procera (Roxb.) Willd. (1806), Mimosa elata Roxb. (1832). Vernacular names White siris, forest siris (Australian standard trade name), tall albizia (En). Indonesia: ki hiyang (Sundanese), wangkal, weru (Javanese). Malaysia: oriang. Papua New Guinea: brown albizia. Philippines: akleng parang. Burma (Myanmar): sit, kokko-sit. Cambodia: tramkâng', tronum' kâmphé:m. Laos: tho:nx. Thailand: thingthon (central), suan (northern, north-eastern). Vietnam: mu[oof]ng xanh. Origin and geographic distribution A. procera occurs naturally from India, throughout South-East Asia to northern Australia, extending northwards to southern China, including Hainan and Taiwan. It does not occur spontaneously in Peninsular Malaysia and has been collected only once in Borneo. It has been introduced into a number of African countries and into Panama and Puerto Rico. Uses A. procera is used for amenity planting, wind-breaks, fire-breaks and the rehabilitation of eroded and degraded soils. It is occasionally planted as a shade tree in tea and coffee. A.procera is planted for fuelwood and gives excellent charcoal. The wood is used for agricultural implements, moulding, furniture, veneer, and cabinet work. It is also a substitute for walnut. On mountain slopes in Benguet Province in the

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Philippines the farmers leave A. procera trees untouched when clearing land for crops, as the trees cast only a light shade, add nitrogen to the soil and conserve water, and function as a cash reserve as the wood is sought after by local wood carvers. In India and Nepal the leaves are cut for fodder. In former times the bark provided tanning material. Low tannin content (13%), considerable weight loss in drying and difficult harvesting have limited its importance. The pounded bark is used as a fish poison. In Nepal the leaves are used as an insecticide. Properties Analysis of the mineral composition ofleaves from two-year-old trees grown on an ultisol (pH 4.5) in South Sumatra indicated per 100 g dry material: N 1.76 g, P 0.08 g, K 1.07 g, Ca 0.66 g, Mg 0.28 g, Na 0.01 g, S 0.17 g. Digestibility analysis of this material gave: neutral detergent fibre 64%, acid detergent fibre 65%,ash 4%, lignin 42%, and lipids 5.5%. Under favourable conditions and intensive management in Puerto Rico higher values were found per 100 g dry matter: N 3.3 g, P 0.3 g, K 1.5 g. The amounts of nutrients immobilized in the trunk and branches were also high. The leaf has a high raw fibre and lignin content, indicating poor digestibility. Mineral content of the leaves for N, K, Ca, and Mg is adequate for animal production, but the Na and P contents are inadequate. Use for fodder is therefore recommended only in mixtures with other species. The oil content of the seed is about 7.5%. The weight of 1000 seeds is 30-60 g. A large proportion of the stem is non-durable, straw-coloured to off-white sapwood. The heartwood is deep brown, hard and heavy, with an airdry density of 640-880 kg/m 3 . It is fairly durable when exposed. The wood is diffuse-porous; growth rings are present but inconspicuous. Crystals are present. Energy value is 20 500-21 000 kJ/kg. The wood is resistant to several species of termites, including Bifiditermes beesoni, Cryptotermes cynocephalus and Coptotermes curvignathus, though the latter is reported as a pest of the tree in India. Description Tree with an open canopy, up to 30 m tall with trunk of 35(-60) cm in diameter; bole straight or crooked, up to 9 m. Bark smooth, pale grey-green, yellowish-green, yellowish-brown or brownish with horizontal ridges, sometimes flaking in thin, small scales, underbark green, changing to orange just below the surface, inner bark pinkish or straw-coloured. Branchlets terete, glabrous. Leaves bipinnate with 2-5 pairs of subopposite pinnae; rachis 10-30 cm, glabrous, with a

Albizia procera (Roxb.) Benth. - 1, habit; 2, flowering branch; 3, part of leaf; 4, central flower; 5, marginal flower; 6, pod. gland 1-2.5 cm above the base; gland narrowly elliptical, 4-10 mm long, sessile, flat and disc-like or concave with raised margins; pinnae 12-20 cm long, glabrous, with elliptical glands below the junction ofthe 1-3 distal pairs of petiolules, 1 mm in diameter; petiolule 2 mm; leaflets 5-11 pairs per pinna, opposite, rigidly chartaceous to subcoriaceous, asymmetrically ovate to sub-rhomboid, 2-4.5(-6) cm x l-2.2(-3.2) cm, base asymmetrical, half truncate, half cuneate, apex rounded or subtruncate, often emarginate, mucronate, both surfaces sparsely appressed puberulous, rarely glabrous above. Inflorescence composed of pedunculate glomerules collected in an axillary, sparsely puberulous panicle up to 30 cm long; peduncle (0.8-)1.5-2(-3) cm long, 2-5 together; flowers 1530 per glomerule, sessile, uniform (central flowers usually larger than marginal ones), bisexual, pentamerous; calyx tubular to narrowly funnelshaped, 2.5-3 mm, glabrous, light green, teeth triangular, 0.75-1.2 mm, acute; corolla funnelshaped, 6-6.5 mm long, greenish-white, tube glab-

ALBIZIA

rous, with elliptical lobes of 2-2.5 mm, acute, puberulous at the apex; stamens numerous, united at the base into a tube that is longer than the corolla tube; ovary glabrous. Pod straight, flat, chartaceous, 11.5-20 cm x 2-2.5 cm, glabrous, dark or red-brown, with distinct marks over the seeds, dehiscent. Seed flattened obovoid-ellipsoid, 7.5-8 mm x 4.5-6.5 mm x 1.5 mm; aréole 4.5 mm x 3 mm with pleurogram nearly parallel to the margins ofthe seed. Seed with epigeal germination. Growth and development Though reported to be moderately fast-growing, having a mean annual increment in diameter of 1-4 cm and reaching 40-60 cm diameter at breast height in 30 years in northern India, performance has been very poor in trials in the Philippines (33.8 cm after 3 years) and on ultisols in South Sumatra (less than 1 m after 2 years). During the dry season the tree becomes almost leafless for a short time. In India, flowering starts around June after the onset of the monsoon, ripening of the pods takes approximately 8 months. Elsewhere, it is reported to flower and fruit throughout the year. The tree can be heavily pruned or pollarded to give a bushy crown. A. procera fixes atmospheric nitrogen. Ecology A. procera is commonly found in open secondary forest and in areas with a pronounced dry season. Its habitat ranges from monsoon forest, savanna, pyrogenic grassland, roadsides, dry gullies, to stunted, seasonal swamp forest. It occurs up to 1500 m altitude in the tropics and up to 1200 m in the subtropics. Planting at higher elevations is limited by its susceptibility to frost. The mean annual rainfall is 1700 mm, ranging from 500 mm to 3000 mm, the annual mean minimum temperature is 21°C and annual mean maximum temperature is 32°C. In its natural range in Australia the mean minimum temperature of the coldest month is 11-19°C, the mean maximum temperature of the hottest month 31-34°C. It grows well on shallow soils with a pH of 5.5-7.5, and has a moderate light requirement. In the absence of burning it will colonize alang-alang (Imperata cylindrica (L.)Raeuschel) grassland. Propagation and planting Freshly harvested seed has a germination rate of 90-100%, dropping to below 50% after storage. The seeds retain their viability at least one year. Soaking seed that has been stored for 4-5 months in boiling water for 5 seconds, immediately removing them from direct heat and then soaking them in tap water overnight doubled the germination percentage. In the dry season seed is sown in nursery beds in

drills 20 cm apart, at 5 cm spacing and lightly covered. Direct sowing in the field has proved more successful than transplanting from a nursery, provided regular weeding and loosening of the soil is carried out; line-sowing facilitating weeding has given greatest success. Transplanting of 1-yearold seedlings can be done in the rainy season, preferably during wet weather, with or without pruning. A. procera can be propagated quite successfully by stumps and stem or root cuttings provided that the peaks of the rainy and the dry season are avoided. It may produce root suckers when damaged. Spacing at 2-3 m x 0.5 m in pure stands gives closure of the canopy in about 3 years. Trees which are suppressed in dense stands will die as a result oflack of light. Husbandry Due to the light crown, regular weeding and control of the undergrowth are required. Therefore, A. procera is often mixed with other species and planted at a spacing of 3 m x 1 m. Mixed planting and pruning in open stands can improve stem form. Thinning is necessary after 9 years. Diseases and pests A. procera trees in India and Malaysia have sometimes been defoliated by larvae of Lepidoptera species such as Rhesala imparata, R. inconcinnalis and R. moestalis. In Africa the termite Ancistroterm.es amphidon is a serious pest on young trees. Yield Annual wood production of about 10 m 3 per ha has been recorded from Java. A4-year trial on an ultisol of pH 4.5 at Nakau, South Sumatra showed a very low growth rate when compared to Leucaena leucocephala (Lamk) de Wit, Acacia mangium Willd., and Paraserianthes falcataria (L.) Nielsen. Harvesting of stem and leaves above 1 m height yielded 0.10 and 0.69 kg of wood (fresh weight per tree 36 and 50 months after transplanting of seedlings respectively), and 1.1 kg of dry leaves after 50 months. Prospects Since A. procera grows moderately fast in areas with poor, seasonally swampy, shallow soils and a long dry season and provides good quality wood and excellent charcoal, its potential as an alternative timber and fuelwood species should be further explored. The poor digestibility of its leaves make its usefulness as a fodder questionable. Literature 111 Blair, G.J., Panjaitan, M., Ivory, D.A., Palmer, B. & Sudjadi, M., 1988. An evaluation of tree legumes on an acid ultisol in South Sumatra, Indonesia. Journal of Agricultural Sei-

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ence 111(3): 435-442. 121 Browne, F.G., 1968. Pests and diseases of forest plantation trees. Clarendon Press, Oxford, United Kingdom, p. 1027. 131 Chauhan, A.N., Bhatt, D.N., Mishra, C M . & Singh, S.L., 1986. Root development in some species on usar soils. Journal of Tropical Forestry 2: 119-130. 141 Chauhan, L. & Dayal, R., 1985. Wood anatomy of Indian Albizias. IAWA (International Association of Wood Anatomists) Bulletin, (new series) 6: 213-218. 151Danimihardja, S., Saefudin, F., Syarif, F. & Setyowati-Indarto, N., 1988. Pertumbuhan beberapa jenis Leguminosa tumbuh-cepat di lapangan setelah semainya diinokulasi dengan Rhizobium [The growth of some fast-growing legume species in the field after seedling inoculation with Rhizobium]. Berita Biologi 3: 377-381. 161Nielsen, I.C., 1992. Mimosaceae. (Leguminosae - Mimosoideae). Albizia. In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana. Series 1, Vol. 11. Foundation Flora Malesiana, Leiden, the Netherlands, pp. 64-86. 171 Penafiel, S.R. & Botengan, H.P., 1985. Indigenous agroforestry in Benguet: starting point for research and development. Canopy International 11: 1, 8-9. I8l Rajhkowa, S., 1965. A short note on planting trials with Albizzia procera. Indian Forester 91(12): 845-847. 191 Tumalian, B.T., 1985. Species and provenance trial of selected fuelwood species. Sylvatrop 10(1): 34-48. J.L.C.H. van Valkenburg

A i n us M i l l e r Gard. Diet. abr. ed. 4:51 (1754). BETULACEAE

A. japonica: 2n = 42,A. nepalensis: In =56. Major species and synonyms - Alnus japonica (Thunb.) Steud., Nomencl. bot. ed. 2, 1: 55 (1840), synonyms: A. oblongata Willd. ex Regel (1861), A. formosana (Burkill) Makino (1912), A. maritima (Marsh.) Nuttall (1842). -Alnus nepalensis D. Don, Prodr. fl. Nepal.: 58 (1825). Vernacular n a m e s General name: alder (En). - A.japonica: Japanese alder (En). - A . nepalensis: Indian, Nepal or Nepalese alder (En). Burma (Myanmar): maibau. Origin and geographic distribution Alnus consists ofabout 20(-35) species and is distributed mainly in temperate and subtropical areas of the Old World. A. japonica is a native of Taiwan,

Japan and North-East Asia (China, Korea, Siberia) and is grown in the Philippines. A. nepalensis occurs naturally throughout the Himalayas from Pakistan through Nepal, northern India, Bhutan and Upper Burma (Myanmar) to southwest China and Indo-China. It has been introduced into South-East Asia, with particular success in the Philippines. Trial plantings of both species have been made in Malaysia and West Java. Plantations of A. nepalensis exist in tropical Africa, Costa Rica and Hawaii. Uses As many other Alnus spp.,A. japonica and A. nepalensis are important sources of firewood. They are useful trees in agroforestry, planted to improve the stability of slopes liable to erosion and land-slides and for mine reclamation. Being nitrogen-fixing trees they can improve degraded lands. In Burma (Myanmar) A. nepalensis has been used effectively to reforest abandoned fields. In north-eastern India, Sikkim and Nepal A. nepalensis is interplanted with annual crops and used as a shade tree for greater cardamom (Elettaria subulatum Roxb.) and for Cinchona officinalis L. A. japonica is planted for shade in coffee and as a nurse tree in Pinus kesiya Royle ex Gordon plantations in the Philippines, where it has also been planted for reforestation. It is also grown as living posts supporting a network of wires for chayote (Sechium edule (Jacq.) Swartz), a fruit vegetable. Leaves are used as animal bedding. In the Philippines A. japonica has been found to be suitable as bed logs for shiitake mushroom (Cortinellus shiitake) cultivation, and is also grown as an ornamental. A. nepalensis is pollarded for poles and its wood is used for boxes, match splints and for general carpentry, furniture parts, turnery, as well as for newsprint pulp and the production of charcoal. It is suitable as core material for plywood. The wood of A. japonica is suitable for making furniture, tools and packaging, and for the production of charcoal for gunpowder. The bark ofA. nepalensis has been used occasionally for tanning and dyeing. Its foliage is of low to moderate value as fodder for sheep and goats, but not suited for cattle. Properties Considerable quantities of nutrients are recycled through the litter ofAlnus spp. Leaf and twig litter ofA. nepalensis, grown in the eastern Himalayas and producing annually 3-6 t/ha litter, contains per 100 g dry matter: N 3.4-3.7 g, P 0.08-0.10 g, K 0.6-0.7 g, Ca 0.2 g. The wood ofA. nepalensis is moderately soft and lightweight with a density of 320-590 kg/m3. Its

ALNUS

energy value is low (18 230-20 480 kJ/kg), but, like that of other alders, the wood dries rapidly and burns easily. The wood is pale brown or superficially bronze-coloured, with low lustre. Grain is variable, texture medium to fine. Although not among the best construction timbers, A. nepalensis seasons without excessive warping or splitting, but shrinkage figures are high. It is easy to saw and finish by hand or machine, with only slight blunting effects on tools. Planing and boring give good results while mortising and turning results are only fair with some picking up of grain. The wood preserves fairly well, but is non-durable in exposed conditions and is susceptible to discolouration by oxidation and fungal sap staining. The wood ofA.japonica is largely similar to that ofA. nepalensis; it shows slight discolouration by sunlight. In the Philippines, kraft pulping of wood of an Alnus sp. showed a pulp yield of 47.6%. Bleaching improved the brightness to 76%. The pulp was suitable for the manufacture of good quality paper. Seeds are very small: 1000 seeds ofA. nepalensis weigh 0.28-0.43 g, seed ofA. japonica is somewhat larger. Seed weight is sometimes given for seed including chaff, 1000 seeds weighing 8 g for A. japonica. Description Monoecious shrubs and trees with a dense crown; bark generally grey and smooth; twigs with a 3-angled pith and stalked, perular buds. Leaves simple, alternate, in 3 rows, mostly with domatia in the vein axils and often glandular-lepidote below; stipules early caducous. Flowers in unisexual catkins. Male inflorescence a many-flowered pendulous catkin; flowers arranged in groups of 3 (triads) in the axil of a bract; flower with 4 perianth segments mostly connate at base; stamens 4, epipetalous, with short filaments. Female inflorescence a short, upright catkin; flowers in groups of 2 (diads) sustained by a bract concrescent with 4 bracteoles, without a perianth; styles 2 with stigmatose tip. Fruiting catkin cone-like, woody, with 5-lobed scales and minute 2-winged nutlets. Fruit a small nut, compressed, 1-seeded, crowned by the styles. Seed without endosperm. - A . japonica. A deciduous or evergreen shrub or small tree, 3-10(-20) m tall; twig ends rather sharply triangular, glabrous or subglabrous. Leaf blade ovate-oblong to elliptical-oblong, 6-9.5(-13) cm x 2.7-5 cm, dentate, distinctly acuminate, base broadly or obtusely cuneate or subrotundate, with 6-7 pairs of lateral veins;

Alnus japonica (Thunb.) Steud. - 1, flowering branch; 2, fruiting branch; 3, triad of staminate flowers with anther; 4, female catkin; 5, diad of female flowers; 6, winged nutlet. petiole slender, 1-3 cm long. Male catkin 3-5 cm x 3-5 mm. Female catkins arranged in a terminal raceme on short shoots; catkin 1.5-2.5 cm x 1 cm; peduncle 0.5 cm long. Nut obovate-orbicular, not emarginate, about 3 mm in diameter including the wings. - A . nepalensis. A deciduous or semideciduous tree, 8-15(-33) m tall, trunk straight, up to 80(-200) cm in diameter; twigs ribbed, glabrescent; bark thick, dark green or grey to silvergrey, often with yellowish patches and short, raised lenticels. Leaf blade ovate to oblong, 6-21 cm x 4-10 cm, shallowly crenate to subentire, acute to shortly acuminate, rounded or cuneate at the base, with 12-16 pairs of lateral veins; petiole strong, 1.5-2 cm long. Male catkins grouped in a terminal panicle up to 16 cm long; catkin 10-16(-25) cm long, yellow. Female inflorescences grouped in a short, axillary raceme of 3-8 catkins; catkin 1.0-1.7 cm x 0.6-0.7 cm; peduncle 3-6 mm long. Nut obtrapezoid, emarginate, 2mm in diameter including the wings.

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Growth and development Both Alnus species develop an extensive lateral root system and are fast growing. Diameter growth of A. japonica is faster in open areas than in shade, while height growth is faster in shade. For A. nepalensis a mean annual diameter increment of 2 cm is not rare and an annual increment of 2.7 m in height and 2.9 cm in diameter have been recorded in Nepal. Exceptionally high annual increment figures of 4 m in height and 5 cm in diameter have been reported for A. japonica in the Philippines. Growth rates vary considerably, particularly in response to soil moisture and altitude. A. japonica is shade tolerant and tends to retain its lower branches. While it is deciduous in Japan, it seems evergreen in the Philippines. Under flooded conditions A. japonica retains its leaves and can almost maintain its growth rate by forming adventitious roots with abundant aerenchyma. A. nepalensis and A. japonica form a symbiosis with N-fixing actinomycetes ofthe genus Frankia. In its natural habitat A. japonica flowers and fruits from April to November, A. nepalensis from November to March, depending on geographical locality. Other botanical information A. japonica is sometimes considered to be different from the American A. maritima (Marsh.) Nuttall. A. maritima would have leaves that are more elliptical to obovate.A. japonica specimens from Taiwan have been accommodated in a separate variety (A. japonica (Thunb.) Steud. var. formosana (Burkill) Callier or A. maritima (Marsh.) Nuttall var. formosana Burkill) or even a distinct species (A. formosana (Burkill) Makino), but at present they are not considered different from A. japonica. The tropical American A. acuminata O. Kuntze (synonym A. jorullensis Kunth) is occasionally tested as an alternative toA.japonica and A. nepalensis. It grows under comparable conditions. Pollination and seed dispersal ofAlnus spp. are by wind. Ecology As pioneers, A. japonica and A. nepalensis grow well in full sunlight although shade is tolerated. A. nepalensis is found naturally in moist, cool, subtropical mountain monsoon climates, with a mean annual rainfall of 800-2500 mm and a dry season of 4-8 months. It occurs naturally at altitudes of 1000-1800(-3000) m, but it has been planted down to 300 m. Mean annual temperatures range from 13-26°C. Alnus spp., including the 2 species discussed, occur mainly in wet soils along streams and in swamps and also on exposed soils. A. nepalensis prefers moist and

well-drained soils, varying from loam and loamy sand to gravel, sand and clay. It can withstand some imperfect drainage but does not tolerate prolonged periods of waterlogging. It grows poorly on dry, exposed ridge-tops. A. japonica occurs naturally in marsh or swamp forest in Japan with a generally high water table, and soil conditions tending to be anaerobic with high clay and organic matter contents.A.japonica does not require very fertile soil, but prefers permeable soils and should not be planted in compact soils. Propagation and planting A. nepalensis is readily grown from seed, but may also be propagated vegetatively by tissue culture. Seed will retain its viability for at least a year if properly dried and stored in sealed containers. Likewise,A. japonica seeds retain their viability for 3-6 months. Fruits are collected from the trees and seed is released when fruits are left to dry in the sun. No pretreatment is needed. The fine seeds are broadcast in beds. Germination starts 1-2 weeks after sowing and is completed 2 weeks later. Transplanting seedlings into containers can begin 4-5 weeks after germination. Below 1200 m elevation seedlings reach a planting size of 25-35 cm in 4-5 months, but at higher altitudes they may take as long as 11 months. Young seedlings are liable to damage by ants and defoliation as a result of frost. Their survival rate is often very low. Most planting of A. nepalensis is done with containerized seedlings, although bare-rooted seedlings have proven successful provided lifting and handling is done properly and moisture availability is high at the planting site. In the Philippines bare-rooted seedlings ofA.japonica are generally used. Wildlings of A. nepalensis have been used successfully in Nepal, especially on north-facing slopes. Direct sowing is an alternative, even on exposed mineral soils. Seed must be fresh, as then it has a high germination rate. Ample quantities should be used. Good results are obtained when seed is mixed with soil from under old trees to facilitate even broadcasting and to introduce Frankia inoculum. Clonal micropropagation is feasible on a commercial basis for A.japonica, but other vegetative propagation methods have not been successful. Planting out stock ofA. japonica of 30-45 cm tall is recommended for the Philippines in areas with altitudes over 600 m and a rainfall of less than 50 mm/month during 4-6 months. A spacing of 2.5 m x 2.5 m is commonly used for plantations of A. nepalensis in Nepal, although a

AZADIRACHTA

closer spacing is desirable for fuelwood crops. In the Philippines, A. japonica is planted at 15 m x 15 m to provide shade for coffee planted at 2 m x 2 m. Husbandry After coppicing, regrowth is best when felling is done during the wet season and in moist localities. Alnus spp. are highly susceptible to wind damage. Trials in East Java with A. nepalensis were not successful because of a mortality rate of 95-100%. A. japonica shade trees in coffee plantations are pruned to a height of 3-5 m and branches are used as fuelwood. It is sufficiently tolerant of shade to be planted in Pinus kesiya stands transmitting as little as 30% light. A. japonica is reported to coppice easily and to be fire-sensitive. On fertile sites poles and fuelwood can be harvested after 5 years. Small-diameter timber can be harvested in less than 10 years. Diseases and pests A. nepalensis is very susceptible to attacks by defoliators (Anomala spp., Oreina spp.). Stem borers (Batocera spp. and possibly Zeuzera spp.) may also become pests. An aphid (Eutrichosiphum alnifoliae) is a pest of economic importance. Where A. japonica is introduced it suffers only very mild attacks by the sawfly (Fenusa dohrnii) compared with other Alnus spp. In Japan A. japonica is a host for Eotetranychus tiliarium, while in China both the larvae and adults of Agelastica coerulea feed on its leaves. Yield In northern India the yield ofA. nepalensis grown in plantations for timber and ranging in age from 7-56 years was estimated. When 7 years old and with a plant density of 715 trees/ha, bole biomass was 53 m 3 /ha, at 17 years with 545 trees/ha bole biomass had increased to 138 m 3 /ha, and at 56 years with 435 trees/ha it had reached 394 m 3 /ha. Breeding Research in Nepal on A. nepalensis has shown that local provenances perform best at any given site. None of the provenances, however, showed overall superiority. Interspecific crosses with the black alder, A. rubra Bong., have been made. Prospects As Alnus spp. are capable of fixing atmospheric nitrogen, they have the ability to enrich soils. They are generally well suited for reforestation purposes, particularly in moist areas, and for improving soil fertility. On unstable slopes their extensive lateral root system contributes to watershed protection and erosion control. Further research into the genus seems appropriate as, to date, the full potential ofthese multipurpose trees

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in forestry and agroforestry has still to be uncovered. Literature 111 Costales, E.F., Jr. & Costales, A.B., 1985. Effects of plant combination on the protection/stabilization of mined waste areas. Sylvatrop 10: 187-201. I2lJackson, J.K., 1987. Manual of afforestation for Nepal. XII. Nepal-UK Forestry Research project, Kathmandu, Nepal, pp. 190-193. 131Neil, P.E., 1990. Alnus nepalensis: A multipurpose tree for tropical highlands. NFT Highlights, NFTA 90-06, November 1990. Nitrogen Fixing Tree Association, Waimanalo, Hawaii, United States. 2 pp. I4l Penafiel, S.R., 1985. Growth of Japanese alder (Alnus japonica Nutt.) under two methods of inoculation. Sylvatrop 10: 69-75. 151 Penafiel, S.R., Noble, B.F. & Ngales, L.P., 1982. Growth of Benguet pine (Pinus kesiya Royle ex Gordon) seedlings planted under alnus (Alnus japonica Nutt.) stand. Sylvatrop 7: 45-48. 161 Ramoran, E.B. & Panot, I.A., 1981. The potentials of Alnus species - Let's harness them. Canopy International 7(12): 8-9. I7l Sharma, E., 1993. Nutrient dynamics in Himalayan alder plantations. Annals of Botany 72: 329-336. I8l Sharma, E. &Ambasht, R.S., 1991. Biomass, productivity and energetics in Himalayan alder plantations. Annals of Botany 67: 285-293. l9l van Steenis, C.G.G.J., 1955. Betulaceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana. Series 1, Vol. 5. Noordhoff-Kolff, Djakarta, Indonesia, pp. 207-208; Vol. 6, p. 917. llOl Yamamoto, K., Sakata, T. & Terazawa, K , 1995. Growth, morphology, stem anatomy, and ethylene production in flooded Alnus japonica seedlings. IAWA (International Association of Wood Anatomists) Journal 16(1): 47-59. P.E. Neil

Azadirachta indica A.H.L. Juss. Mém. Mus. Nat. Hist. Nat. Paris 19: 221, t.13, fig. 5(1832). MELIACEAE

2re =28, 30 Synonyms Melia azadirachta L. (1753), M. indica (A.H.L. Juss.) Brandis (1874), Anteiaea azadirachta (L.)Adelb. (1948). Vernacular n a m e s Neem, Indian lilac, margosa tree (En). Neem (Am). Azadirac de l'Inde, margosier, margousier (Fr). Indonesia: mimba (Java), membha (Madura), intaran (Bali). Malaysia: baypay, mambu, veppam (Peninsular). Papua New Guinea: neem. Philippines: neem. Singapore:

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AUXILIARY PLANTS

kohomba, nimba, veppam. Burma (Myanmar): tamarkha, thinboro, tamar. Cambodia: sdau. Laos: kadau. Thailand: khwinin (general), sadao (central), saliam (northern). Vietnam: sfaaflu d[aa]u. Origin and geographic distribution The exact origin of neem is unknown. It is thought to have originated in the Assam-Burma (Myanmar) region and to be distributed naturally throughout the Indian subcontinent. It has long been cultivated in Peninsular Malaysia, Indonesia and Thailand, where it is completely naturalized and has modified deciduous forests. In the 19th Century South Asian emigrants took it to Fiji, Mauritius and Guyana, and the British to Sudan, Egypt, East Africa, and sub-Sahel West Africa, where it is widely grown and has also naturalized. It has recently been introduced into tropical South and Central America, Florida, Hawaii, Saudi Arabia, the Philippines, and northern Australia. Now it is probably one of the fastest-spreading trees and has become pan-tropical. U s e s Neem is a multipurpose tree, grown for shade and shelter, for timber and fuel, to control erosion and improve soils, while the oil from the seed is used in soap manufacturing. In the Indian subcontinent it is most famous for its medicinal and insecticidal properties. The large crown of neem makes it an effective shade tree, planted widely as an avenue tree in towns and villages and along roads in many tropical countries. Recently, 50 000 neem trees have been planted in the Arafath plane near Mecca in Saudi Arabia, to provide shade to Muslem pilgrims. Because of its low branching, neem is grown as a wind-break. In South-East Asia it is mainly planted to protect and improve very poor soils. In East Java, neem trees are tapped to extract gum exudates used for making paper glue. The tree's hard, termite-resistant wood is used in construction, for making carts, agricultural implements and furniture, and is suitable for the manufacture of plywood and blockboard. It makes a good firewood and is extremely important as fuel for example in West Africa. Neem twigs are commonly used to clean teeth, whereas young twigs and young flowers are occasionally consumed as a vegetable. The leaves, though very bitter, are used as a dry season fodder. Neem seed oil is used in South Asia for soap making. The residue after oil extraction or 'neem cake' serves as livestock feed and fertilizer. Recently, it has been used as an admixture or coating of urea fertilizer to reduce losses of N from urea through denitrification.

Neem is best known for its medicinal uses, described early on in classical Hindu texts, and detailed in the Ayurvedic and Unani schools of medicine. People bathe in water with neem extracts to treat health problems. Various parts have anthelmintic, antiperiodic, antiseptic, diuretic, and purgative actions, and are also used to treat boils, pimples, eye diseases, hepatitis, leprosy, rheumatism, scrofula, ringworm and ulcers. In Africa neem leaves are chewed and an infusion from the leaves is taken to prevent conception and induce abortion. In modern medicine, antibacterial, antifungal and anti-inflammatory effects have been demonstrated, but are still in the early stages of testing. Small but significant effects against malaria parasites have been found and the active chemicals have been isolated. Preliminary experiments indicate that neem-seed extracts may contribute to the control of Chaga's disease, a nerve disease affecting about 20 million people in Latin America caused by Tripanosoma cruzi, a parasite related to the cause of the African sleeping sickness, and transferred by kissing bugs (Rhodnius spp.). The extracts mainly act by repelling the vector, but also by interfering with its moulting and by killing the parasites in the vector. Neem oil has a strong spermicidal action and possibly prevents the implantation of the ovule. A neem oil-based product 'Sensal' is being marketed in India as an intravaginal contraceptive. The tree's upcoming promise builds upon its traditional use for pest control, especially of storage insects. In northern India neem leaves are mixed with legume or cereal grain to prevent insect damage. More than 200 species of insects, mites, and nematodes, including destructive crop pests are controlled by extracts from leaves, seed, bark, or flowers. Over 30 pesticides based on azadirachtin, one of neem's many biologically active components, are being marketed and several have been registered by the Environmental Protection Agency ofthe United States. Commercial products are also available against lice and fleas of animals. Mosquito-repellent coils are among neem's other emerging uses. Production and international trade In India more than 18 000 t of neem-seed oil is used for soap making. Assuming a fruit yield of 25 kg per tree and an oil content of 10%, this oil must come from about 7.2 million trees. Less than 25% of India's neem trees (in 1975:25 million) are currently exploited. International trade seems limited to small quantities of leaves imported by two American companies manufacturing neem-based pesti-

AZADIRACHTA

cides. Neem oil is valued at about US$ 700/t (1990). Properties Neem seed contains 20(-50)% oil. The oil (and to a lesser extent the leaves) contain many biologically active tetranortriterpenoid compounds, especially limonoids. The following groups of limonoids are the most important: azadirachtin, meliacarpin, nimbin, nimbolinin and salannin. Azadirachtin (C 25 H 44 0 16 ), a steroid-like, highly oxidized tetranortriterpenoid, structurally similar to insect hormones (ecdysones), has deterrent, antifeedant, anti-ovipositional, growth-disrupting, fecundity and fitness-disrupting properties in insects and several other groups of animals. By blocking the release of these hormones, azadirachtin appears to disrupt the moulting cycle ofthe insects. Azadirachtin concentrations in seed range from 2-4 mg/g, a maximum of 9 mg/g is reported from Senegal. Biological activity appears greater in trees from drier areas. In hot climates, the azadirachtin concentration is lower. However, the relative roles of genetic and environmental factors are not yet clear. The other compounds of neem are less well studied. Compounds of the azadirone, gedunnin, meliacarpin, nimbin, salannin and vilasinin groups of tetranortriterpenoids appear to be powerful feeding inhibitors, while the nimbolinins and gedunnins have growth-disrupting properties. Compounds of the nimbin group are also bactericidal and cytotoxic, while nimbin and nimbolinin may have anti-viral properties. Other chemically important compounds found in neem include glycerides, polysaccharides, sulphurous compounds, flavonoids and their glycerides, amino acids, and aliphatic compounds. The wood of neem is hard and resembles hogany. The density of the wood is 720-930 kg'm 3 at 12% moisture content. The heartwood is »eddish when freshly exposed, but fades in sunlight to reddish-brown, clearly demarcated from the greyish-white sapwood. The wood is aromatic when fresh and beautifully mottled. The grain is narrowly interlocked, medium to coarse in texture and often uneven. The timber seasons well with little degrade. Pre-boring is necessary when nailed. The wood is durable even in exposed situations, and not attacked by termites or woodworm. It is easy to work by hand or machine, but does not polish well. The energy value of the wood is 20 830 kJ/kg. The energy value of neem seed oil is 45 300 kJ/kg. Neem charcoal is of good quality with an energy value only slightly below that of coal. Neem leaves contain per 100 g dry matter: crude

73

protein 12-18 g, crude fibre 11-23 g, N-free extract 43-67 g, ash 8-18 g, Ca 1-4 g, P 0.1-0.3 g. The weight of 1000 seeds is (105-)185-270(-350) gDescription A small to medium-sized, usually evergreen tree, up to 15(-30) m tall with round, large crown up to 10(-20) m in diameter; branches spreading; bole branchless for up to 7.5 m, up to 90 cm in diameter, sometimes fluted at base; bark moderately thick, with small scattered tubercles, deeply fissured and flaking in old trees, dark grey outside and reddish inside, with colourless, sticky foetid sap. Leaves alternate, crowded near the end of branches, simply pinnate, 20-40 cm long, exstipulate, light green, with 2 pairs of glands at the base, otherwise glabrous; petiole 2-7 cm long, subglabrous; rachis channelled above; leaflets 8-19, very short-petioluled, alternate proximally and more or less opposite distally, ovate to lanceolate, sometimes falcate, (2-)3.5-10 cm x 1.2-4.0 cm, glossy, serrate, apex acuminate, base unequal. Inflorescence an axillary, many-flowered

Azadirachta indica A.H.L. Juss. - 1, fruiting branch; 2, part of inflorescence; 3, vertical section through flower.

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AUXILIARY PLANTS

thyrse, up to 30 cm long; bracts minute and caducous; flowers bisexual or male on the same tree, actinomorphic, small, 5-merous, white or pale yellow, slightly sweet scented; calyx lobes imbricate, broadly ovate and thin, puberulous inside; petals free, imbricate, spathulate, spreading, ciliolate inside; stamens 10, filaments fused into a 10-lobed staminal tube, glabrous and slightly ribbed outside, anthers sessile, opposite the rounded to laciniate lobes; disk annular, fused to the base of the ovary; ovary superior, style slender, stigma capitate, 3-lobed. Fruit a l(-2)-seeded drupe, ellipsoidal, 1-2 cm long, greenish, greenish-yellow to yellow or purple when ripe; exocarp thin, mesocarp pulpy, endocarp cartilaginous. Seed ovoid or spherical, apex pointed, testa thin. Seedling with epigeal germination; cotyledons thick, fleshy, elliptical with a rounded apex and sagittate base; first pair of leaves opposite, subsequent pairs either opposite or alternate, first few leaves usually trifoliolate, later 5-foliolate with deeply incised, pinnatifid, or partite leaflets. Growth and development At germination the radicle emerges at the end of the seed and the hypocotyl arches, withdrawing the cotyledons from the ground. Growth in the first year is generally slow, 15-25 cm in height, becoming faster when the root system that forms associations with vasicular-arbuscular mycorrhyzal fungi is developed. Trees may reach 4-7 m after 3 years and 5-11 m after 5 years. The annual biomass increment of neem plantations has been reported at 3-10 m 3 /ha. Under moderately favourable conditions mean annual diameter increment is 0.7-1.0 cm, under optimal conditions 2 cm/year may be reached. In irrigated plantations in India 16-yearold trees reached a diameter of 40 cm. Under cool conditions seedling growth ceases and new shoots appear in spring. Neem trees may start flowering and fruiting at the age of 4-5 years, but economic quantities of seed are produced after 10-12 years. Pollination is by insects. In India, a bitter-tasting honey is produced. Certain isolated trees do not set fruit, suggesting that self-incompatibility occurs. The flowering and fruiting season largely depends on location and habitat. In Thailand neem trees flower from December to February and fruit in March to May. Fruits ripen in about 12 weeks from anthesis and are eaten by bats and birds which distribute the seed. Neem trees can live for over 200 years. They are normally evergreen, but may shed all or part oftheir leaves under extremely hot and dry conditions. Timing and duration of leaf shed-

ding, flowering and seed set vary across geographic zones and provenances. Other botanical information The genus Azadirachta A. Juss. is morphologically and anatomically closely related to Melia L., from which it can be easily distinguished by its simply pinnate leaves (bipinnate in Melia). Azadirachta has 2 species: A. indica and A. excelsa (Jack) Jacobs. The latter is a larger tree with larger leaves having 14-23 leaflets with entire margins, occurring naturally in Malaysia, the Philippines, Indonesia and New Guinea and producing valuable timber. In Thailand, 2varieties ofthe neem tree are sometimes recognized: var. indica, referred to as 'sadao India', and var. siamensis Valeton, called 'sadao Thai'. The latter grows wild and is widely distributed in the country; its branches are directed upright, contrary to the more spreading habit of var. indica. Opinions about their taxonomie status vary. Flora Malesiana reduced them to synonyms ofA. indica, other sources have proposed to raise them to species rank. The two varieties can easily be crossed. Ecology Neem grows under a wide range of conditions. It is found naturally from 0-700 m altitude, but can grow at elevations up to 1500 m. In the Philippines neem growing is largely restricted to the southern islands, as trees are too severely damaged by typhoons in Luzon. Mean annual minimum temperatures may range from 9.524.0°C, mean annual maximum temperatures from 26.3-36.7°C. Adult neem trees tolerate some frost, but seedlings are more sensitive. Optimal growth has been observed in areas with an annual rainfall of about 1000 mm, but rainfall may vary from 400-1400 mm. On well-drained soils, up to 2500 mm rainfall is tolerated, but then fruiting is generally poor. Neem does not tolerate waterlogging. Soil textures suitable for neem may range from pure sand to heavy clay. The soil pH may vary between 3 and 9, but best growth occurs on soils with a pH of 6.2-7.0. Neem prefers mediumtextured fertile soils, but still performs better than most other species on shallow, poor soils, or on marginal sloping and stony locations, including crevices in sheer rock. It is occasionally found on moderately saline soils, and has been planted in former sugar-cane plantations abandoned because ofincreasing soil salinity. Under natural conditions neem does not grow gregariously. In India, it is present in mixed forest with Acacia spp. and Dalbergia sissoo Roxb. ex D O ; in Indonesia, naturalized in lowland mon-

AZADIRACHTA

soon forest. In Africa it is found in evergreen forest and in dry deciduous forest. Propagation and planting Neem is generally propagated by seed, but can also be propagated vegetatively by air layering, root and shoot cuttings, grafting, marcotting and tissue culture. Although it is best to harvest the ripe fruits from the tree, fruit collection within 1-2 days of natural dropping also gives satisfactory results and is more practical. The fruits are soaked in water for 1-2 days, depulped and the seeds are dried under shade, and stored in a cool well-ventilated place in cloth or gunny bags. They should not be stored in airtight containers or plastic bags, but should be sown as soon as possible. Mature seeds germinate readily within a week, with a germination rate of 75-90%. Seed remains viable for 4-8 weeks only, but storage ofcleaned and dried seeds at 15°C will prolong this period up to 4 months. Kernels (depulped fruits) stored at -20°C retained their viability for as long as 10 years. Seed is normally sown in the nursery in lines at 15-20 cm x 2.5-5 cm, in a sunny place and covered lightly with soil or mulch. Damage by insects or birds eating the radicles can be prevented by covering with netting or by sowing at a depth of 2.5 cm. Seed beds should be watered sparingly and soil should be kept loose to prevent caking. In frost-prone areas seedlings should be protected by a screen. Seedlings are thinned to 15 cm x 15 cm when 2 months old. When they are 7-10 cm tall, with a taproot of about 15 cm long (about 12 weeks old), they are planted out in the field. Direct sowing in sunken beds, trenches, or on ridges also gives satisfactory results. Intercropping neem with pearl millet (Pennisetum glaucum (L.) R. Br.) has given good results in northern India. Neem propagation by root suckers and stem cuttings can be done using 1000 ppm indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA), and by air layering using IBA or naphtalene-1-acetic acid (NAA). Tissue culture is being tried; fresh cotyledons have been found to be the best source of material. Husbandry Under favourable moisture conditions natural regeneration of neem is usually profuse, as seed is widely distributed by bats and birds. Weeding of neem plantations in dry areas is essential, as it cannot withstand competition, especially from grasses. Neem responds well to organic and chemical fertilizers. In West Africa rotation of neem plantations for firewood is 7-8 years at a final spacing of 5 m x 5 m; on good soils with adequate moisture in Haiti it is planted at 2.5 m x

75

2.5 m and managed with a rotation of only 4 years. As neem coppices well no replanting is necessary after harvesting. Moreover, coppicing is preferred for firewood production, as it facilitates harvesting and management of the plantation. Neem withstands pollarding well, a valuable asset for the use in wind-breaks, but seed production is adversely affected when trees are lopped for fodder. Diseases and pests There are no records of fungi attacking neem in South-East Asia. In India and elsewhere Pseudocercospora subsessilis is the most common fungus attacking the leaves of neem, causing a shothole effect. In India, the bacterium Pseudomonas azadirachtae may damage leaves and a shoot borer damages shoots. Generally, neem appears not to be affected seriously by pests. In South and South-East Asia minor damage is caused by torticid moths (Adoxophyes spp.). Stored neem kernels have reportedly been damaged by Oryzaephilus larvae in India, and by Carpophilus dinudiathus in Ecuador. Recently, a serious decline of neem has been observed in West Africa. Older foliage is shed, leaving crowns with an open appearance. Tufts of leaves remain at the branch apices, for which the disorder is now known as 'giraffe neck'. Preliminary observations indicate that the decline is not caused by a biotic agent, but is due to site-related stress (e.g. inadequate soil moisture, soil compaction, competition). In the state of Bornu in Nigeria, 80-95% ofthe neem trees have been seriously affected. Harvesting The harvesting period of fruits is usually limited to 6-8 weeks after the monsoon rains. Leaves may be collected at any time. Pollarding is usually done on 5-10-year-old trees. Yield Fruit yield is 10-30 kg/tree annually. Neem plantations in Thailand with a spacing of 2-4 m x 4 m yielded annually 6-7.5 m 3 wood per ha in the first 10 years on poor sites and 33-36 m 3 /ha on favourable sites. Handling after harvest Fruit collected for the extraction of neem oil is depulped immediately after collection, and the stones are dried in the shade and stored in a cool, dry place to avoid deterioration by oxidation, a reduction of the azadirachtin content and aflatoxin production by fungal growth. Properly dried stones can be stored for 8-12 months before oil extraction. Genetic resources Germplasm collections are made, maintained, evaluated and distributed by Winrock International Institute for Agricultural Research in Thailand (Bangkok). Seeds are avail-

76

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able commercially e.g. in India, at a price of US$ 0.50-1.00 per kg, excluding freight and certification, and cuttings cost US$ 50 per 100. Breeding Phenotypically superior neem trees have been vegetatively propagated in Australia, India and Thailand. FAO and DANIDA have established provenance trials in Africa, Asia and South America. Prospects Neem is an excellent multipurpose tree candidate for reforestation programmes. It is well adapted to depleted soils, is tolerant of repeated coppicing and pruning for firewood and a source of valuable oil. The quest for environmentally safe pesticides is increasing and neem's chemical properties provide an excellent source for further exploration. Ideally, neem pesticides should be based on crude extracts containing many of its compounds, rather than on single, refined and concentrated ingredients. Literature 111 Ahmed, S. & Grainge, M., 1986. Potential ofthe neem tree (Azadirachta indica) for pest control and rural development. Economic Botany 40: 201-209. 121 Kijkar, S., 1992. Handbook: Planting stock production of Azadirachta spp. at the ASEAN-Canada Forest Tree Seed Centre. ASEAN-Canada Forest Tree Seed Centre Project, Muak-Lek, Saraburi, Thailand. 20 pp. 131 Mabberley, D.J. & Sing, A.M., 1995. Meliaceae. Azadirachta. In: Kalkman, C. et al. (Editors): Flora Malesiana, Series 1,Vol. 12(1). Foundation Flora Malesiana, Leiden, the Netherlands, pp. 341-343. 141Read, M.D. & French, J.H. (Editors), 1993. Genetic improvement of neem: Strategies for the future. Winrock International Institute for Agricultural Research, F/FRED Project, Bangkok, Thailand. 194 pp. I5l Ruskin, F.R., 1992. Neem. A tree for solving global problems. National Academy Press, Washington, D.C., United States. 141 pp. 161Schmutterer, H. (Editor), 1995. The neem tree Azadirachta indica A. Juss. and other meliaceous plants: sources of natural products for integrated pest management, medicine and industry and other purposes. VCH, Weinheim, Germany. 696 pp. 171 Tewari, D.N., 1992. Monograph on neem. R.P. Singh Gahlot for International Book Distributors, Dehra Dun, India. 279 pp. 181 Tampubolon, A.P. &Alrasyid, H., 1989. The neem tree and its developmental prospects in rainfed zones in Indonesia. Duta Rimba 15(109-110): 9-12. S.Ahmed &Salma Idris

B r u g u i e r a c y l i n d r i c a (L.) B l u m e Enum. PL Javae 1:93 (1827). RHIZOPHORACEAE

2n = unknown Synonyms Rhizophora cylindrica L. (1753), R. caryophylloides Burm.f. (1768), Bruguiera caryophylloides (Burm.f.) Blume (1827). Vernacular names Black mangrove (En). Indonesia: tanjang, tanjang sukun (Java), lindur (Madura). Malaysia: berus (general), bakau belukap, berus ngayong (Sarawak). Philippines: pototan lalaki (general), bakâuan (Tagalog), kalapfnai (Ilokano). Thailand: thua-daeng (Chanthaburi), thua-khao (Ranong, Krabi), rui (Phetchaburi). Vietnam: v[ej]t khang. Origin and geographic distribution Bruguiera cylindrica occurs naturally in mangroves from India and Sri Lanka throughout South-East Asia to northern Queensland. It is also occasionally planted. U s e s The wood of B. cylindrica is a commonly used as firewood, for making charcoal and in temporary construction. The bark is said to be of some value for tanning. In Malaysia and Indonesia young hypocotyls are occasionally boiled and eaten as a vegetable or preserve, mainly in times of famine. In Vietnam young shoots are served as a salad. Production and international trade The wood is mainly gathered from natural stands or from cultivated trees in reforestation areas. No statistics are available on its production and trade. Properties The heartwood is reddish to reddish-brown upon exposure, hard, very heavy and strong, with a density of 840-1000 kg/m 3 at 15% moisture content. It is straightly grained and finely textured. Growth rings are indistinct or absent. The logs shrink and check excessively in seasoning, while the wood is easy to work and finishes well. It is non-durable when exposed to weather or in contact with the ground. The wood is lighter in weight and colour than Rhizophora wood, but both genera are traded together. Botany A shrub or tree up to 23 m tall, stem diameter 20-30 cm; buttresses small, up to 1m tall; bark surface grey, warty, with few, small, corky lenticels, inner bark evenly yellow; pneumatophores abundant, knee-like, forming new horizontal and anchor roots. Leaves decussately opposite, elliptical or oblong to oblong-lanceolate, 4-17 cm x 2-8 cm, entire, thin, bright green, apex acute, base cuneate, glabrous, usually with about

BRUGUIERA

Bruguiera cylindrica (L.) Blume - 1, flowering branch; 2, 3-flowered cymose inflorescence; 3, petal after pollen release; 4, viviparous fruit with hypocotyl. 7 pairs of distinct veins on both surfaces; petiole 1-4.5 cm long; stipules in pairs, 2.0-3.5 cm long, early caducous. Inflorescence a cyme, 2-3 flowered; peduncle 6-8 mm long; pedicel 1-4 mm long; flowers greenish, at anthesis 10-12 mm long; calyx tube not ribbed, 4-6 mm x 2 mm, ending in 8 lobes as long as the tube; petals 8, 3-4 mm long, 2lobed, white, soon turning brown, each lobe with 2 or 3 bristles at the apex, outer margins usually fringed with white hairs at the lower parts; each petal embraces a pair of stamens; stamens 16, 1.5-2.5 mm long; ovary inferior, style filiform, 3-4 mm long. Fruit a berry, enclosed by the persistent, sometimes enlarged calyx tube, 10-12 mm long; calyx lobes reflexed, not accrescent; hypocotyl cylindrical, often curved, 8-15 cm x 0.5 cm, grooved or angled, blunt, perforating the apex of the fruit and falling with it. Seed solitary, produced in large quantities. In common with other members of the mangrove species ofthe Rhizophoraceae, the fruits are viviparous. In B. cylindrica the seed not only forms a

77

hypocotyl, but may develop a considerable, rudimentary root system, while still hanging on the tree. In southern Thailand propagules develop for 3-4 months on the mother tree. The seedling still attached to the fruit drops from the tree, embedding itself in the mud, or floating to where it is washed up on the beach. If sufficient light is available trees start flowering when 3-4 years old. Pollen is discharged explosively after being triggered by small insect visitors. B. cylindrica grows under very harsh conditions and is known as the slowest-growing commercially used tree species in Malaysia. It takes over 10 years to reach a height of 6 m and over 15years to attain a height of 9 m and a stem diameter of 6 cm. At the age of60 years it has normally attained about 20 cm in diameter. In old naturally regenerated mangrove forest in Peninsular Malaysia the mean annual diameter increment was estimated to be 0.22 cm. Growth of one-year-old seedlings established in the open in mangrove forests in South Thailand was more than 10 times that of seedlings established in the shade. Ecology In Malaysia B. cylindrica occupies the highest parts of the mangrove forest along the seacoast, where flooding is occasional only, up to about 20 m above sea level. It is usually absent from mangroves along rivers. On stiff clay soils behind the Avicennia zone, it grows gregariously, being one of the most tolerant species of anaerobic soil conditions. Towards the landward side of mangroves it remains as a scattered tree. On better drained soils it gives way to other species. Where land accretion occurs along the coast, it is a precursor ofRhizophora spp. In New Guinea, it is associated with Rhizophora apiculata Blume, R. mucronata Poiret, Bruguiera sexangula (Lour.) Poiret and Nypa fruticans Wurmb in the mangrove-fresh-water swamp transition zone. The very poorly aerated soil habitually occupied by B. cylindrica makes the trees highly dependent on their pneumatophores for an adequate supply of oxygen and particularly susceptible to prolonged submersion. Husbandry As B. cylindrica is such a prolific seed-bearer a healthy forest normally regenerates, even after clear-felling. Wildlings may be collected and used for planting, but regeneration has, so far, been left to nature in most cases. Young, pure stands can be extremely dense and may contain 55 000-70 000 stems per ha. Due to its extremely slow growth rate it requires a very long harvesting cycle. Its rotation should be longer

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than the 20 years now generally practised. Harvesting is done manually with an axe or matchet. This minimizes disturbance to the mangrove. Young trees from short-term rotations are preferred. Average annual wood production ranges from 2-16 m 3 /ha. Prospects B. cylindrica is one of the few economic species growing in brackish, anaerobic soil conditions. It requires and deserves increased research attention to attain its potential. Literature 111 Browne, F.G., 1955. Forest trees of Sarawak and Brunei and their products. Government Printing Office, Kuching, Sarawak, Malaysia, pp. 299-301. 121Duran, L.M. & Figarola, D.B., 1992. Phenological study of some mangrove species ofPhilippine Rhizophoraceae in Punta Dumalag, Davao City, Philippines. CMU (Central Mindanao University) Journal of Science 5: 34-68. I3l Haron Abu Hassan, 1981. The Matang mangrove forest reserve, Perak. State Forestry Department, Perak, Malaysia, pp. 2-18. 141Hou, D., 1958. Rhizophoraceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana, Series 1, Vol. 5. Noordhoff-Kolff, Djakarta, Indonesia, pp. 457-568. 151 Hou, D., 1970. Rhizophoraceae. In: Smitinand, T. & Larsen, K. (Editors): Flora of Thailand. Vol. 2(1). The Forest Herbarium, Royal Forest Department, Bangkok, Thailand, pp. 5-10. 161 Melana, D.M., Melana, E.E. & Arroyo, CA., 1980. Germination study of selected mangrove species. Sylvatrop 5: 207-211. 171 Putz, F.E. & Chan, H.T., 1986. Tree growth, dynamics and productivity in a mature mangrove forest in Malaysia. Forest Ecology and Management 17: 211-230. I8l Tomlinson, P.B., 1986. The botany of mangroves. Cambridge University Press, Cambridge, United Kingdom, pp. 163-170,351. T. Boonkerd &H.T. Chan

B r u g u i e r a s e x a n g u l a (Lour.) P o i r e t Lamk, Encycl. Suppl. 4:262 (1816). RHIZOPHORACEAE

2n =unknown Synonyms Rhizophora sexangula Lour. (1790), Bruguiera eriopetala Wight & Arnott ex Arnott (1838). Vernacular n a m e s Black mangrove (En). Indonesia: bakau tampusing, busing, mata buaya. Malaysia: tumu (putih) (Peninsular, Sarawak), berus putut (Sabah). Philippines: pototan (general), busain, tagasa (Tagalog). Cambodia: plaông prâsak'. Thailand: prasak, phangahuasum-dok-

khao, prasak-nu. Vietnam: v[ej]t, v[ej]t dfufl. Origin and geographic distribution B. sexangula occurs naturally from India and Sri Lanka throughout South-East Asia to New Guinea and New Britain. It has been introduced into Hawaii, where it is now naturalized. Uses Fuelwood, directly or after conversion to charcoal, is probably the main use ofB. sexangula, especially at the local level. Wood from immature plants and branches is usually used for this purpose. The timber ofwell-grown trees is moderately durable and suitable for poles and house construction. It is traditionally also used for fishing stakes. The bark is used as a source oftannin; although it is thinner than the bark of Rhizophora spp., it contains more tannin. The bark also yields a flavouring and an adhesive. In Malaysia and Indonesia the fruit is sometimes used in the betel quid. B. sexangula can be used medicinally, the fruit is applied against shingles, the roots and leaves against burns. In Sulawesi the fruit is cooked, then soaked overnight and eaten, although it is very astringent. Production and international trade No statistics are available on production or trade. Wood is mainly cut from wild stands. Properties The wood of a full-grown tree is heavy, 820-1010 kg/m 3 at 15% moisture content and may have a very attractive colour. It is straightly grained and finely textured, and very strong. The wood is very hard, difficult to saw and work, and finishes well. It is non-durable when exposed to weather or in contact with the ground. Logs shrink and check excessively in seasoning. In the trade it is not distinguished from Rhizophora wood. The energy value of the wood is about 20200kJ/kg. Botany Tree up to 33 m tall, trunk diameter up to 65-80 cm; buttresses up to 1m high, tending to develop into plank-like non-arching stilt roots; pneumatophores knee-shaped, up to 45 cm long, forming horizontal and anchor roots. Bark smooth, greyish to pale brown with a few, large, corky lenticels, especially on the buttresses. Branching mostly sympodial. Leaves decussately opposite, elliptical to elliptical-oblong, rarely oblanceolate, 8-16 cm x 3-6 cm, pale green, entire, acute at both ends; petiole 1.5-5 cm long; stipules in pairs, 3.5-4 cm long, early caducous, green or yellowish. Flowers solitary, generally nodding, at anthesis 2.7-4 cm long; pedicel 6-12 mm long, green, yellow or brownish; calyx tubular with 10-12 lobes, yellow, yellow-brown or reddish, never bright red, tube 1-1.5 cm long and distinctly

CALLIANDRA

Bruguiera sexangula (Lour.) Poiret - 1, flowering branch; 2, flower; 3, petal with enclosed stamen pair; 4,fruit and hypocotyl, with persistent calyx. ridged to the base; petals 10-12, 1.5 cm long, 2lobed, whitish turning yellowish-brown, densely fringed with hairs along the outer margins, lobes half the length of the petal, each with a reflexed and obtuse apex bearing 1-3 bristles, up to 1.2 mm long and a distinct bristle in the sinus between the lobes; each petal embraces a pair of stamens; stamens 7-14 mm long; style filiform, 1.5-2.2 cm long, with 3-4 short branches. Fruit a berry, more or less distinctly ribbed, enclosed in calyx, 1.5-1.8 cm long; hypocotyl cigar-shaped, rather angular, 6-8 cm x 1.5 cm, with narrow blunt end. In common with other members of the Rhizophoraceae, the fruits ofthis species are viviparous. The seedling, still attached to the fruit, drops from the tree, embedding itself in the mud or floating to where it is washed up onthe beach. B. sexangula is the only Bruguiera species which sometimes forms stilt roots. The twigs and petioles lack the white, waxy covering, often characteristic of the closely related B. gymnorhiza (L.)

Savigny that grows more towards the centre of mangrove communities. Ecology B. sexangula occupies the inland parts of the mangrove forests which are not frequently submerged, and may be found along river banks. Occasionally, it is found on sandy shores. It occurs in soils with water that is less saline than seawater, and prefers easily drained soils. In India it is common along the outer fringes of mangrove swamps and sporadic along newly formed canals in their interior. Husbandry In a trial in the Philippines seed germinated 5-10 days after sowing. Harvesting is done manually with axes or matchets, which minimizes disturbance to the mangrove. Young trees from short-term rotations are preferred. Prospects B. sexangula is one ofthe less important mangrove species. It has some economic importance in mangrove vegetation close to the mainland. Literature 111 Backer, CA. & Bakhuizen van den Brink, R.C., 1963. Flora of Java, Vol. 1. Noordhoff, Groningen, the Netherlands, pp. 380-381. 121 Burkill, LH., 1966.A dictionary of the economic products of the Malay Peninsula, 2nd edition. Vol 1. Ministry of Agriculture and Co-operatives, Kuala Lumpur, Malaysia, pp. 379-380. 131 Hou, D., 1958. Rhizophoraceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana, Series 1, Vol. 5. Noordhoff-Kolff, Djakarta, Indonesia, pp. 457568. 141Hou, D., 1970. Rhizophoraceae. In: Smitinand, T. &Larsen, K. (Editors): Flora of Thailand, Vol. 2(1). The Forest Herbarium, Royal Forest Department, Bangkok, Thailand, pp. 5-10. I5l Melana, D.M., Melana, E.E. & Arroyo, CA., 1980. Germination study of selected mangrove species. Sylvatrop 5: 207-211. I6l Tomlinson, P.B., 1986. The botany of mangroves. Cambridge University Press, Cambridge, United Kingdom, pp. 163-170, 349. H.T. Chan &T. Boonkerd

Calliandra calothyrsus Meisner Linnaea21:251(1848). L E G U M I N O S A E - MlMOSOIDEAE

2n = 22 Synonyms Calliandra confusa Sprague & Riley (1923), C. similis Sprague & Riley (1923), C. acapulcensis (Britton &Rose) Standley (1936). Vernacular n a m e s Calliandra, red calliandra (En). Indonesia: kaliandra. Malaysia: kaliandra. Philippines: calliandra.

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Origin and geographic distribution Although originally described from Surinam, where it was probably introduced, C. calothyrsus is native to humid and sub-humid Central America from southern Mexico to central Panama, between 8-19°N. In 1936 it was introduced from Guatemala into Java, where it became well established. In view of its excellent performance in Indonesian plantations it is now planted in other countries of South-East Asia and tested in Africa, Australia, some Latin American countries and Hawaii. Uses In its native area, C. calothyrsus was not known to be useful. However, in Indonesia where it was originally introduced as a green manure crop for timber plantations, it has become favourably known for its many uses. It is primarily grown as a source of small-size fuelwood for household use and small industries, is widely planted for soil improvement, for erosion control on sloping lands and in ravines, and to suppress alang- alang (Imperata cylindrica (L.) Raeuschel). The wood is suitable for charcoal, pulp and paper, and fibre board production. C. calothyrsus is also used in alley-cropping systems as a source of green manure, in planted fallow, and in firebreaks. It has shown promise as an understorey plant in coconut plantations with about 60% light transmission. In forestry it is used as a nurse tree for partially shade-tolerant timber species (e.g. Agathis spp.). It has potential as a high quality source ofleaf protein for supplementing low quality forages and crop residues. Its beautiful red 'powderpuff flowers make it an attractive ornamental, and the flowers produce a good quality nectar for honey. It is a suitable host for the lac insect (Laccifer lacca). Production and international trade During the 1970s, C. calothyrsus became well established in Indonesia, its area increasing from about 60 000 ha in the late 1960s to 170 000 ha by the early 1980s. Properties Leaves ofC. calothyrsus contain per 100 g dry matter: crude protein 22 g, fibre 30-75 g, ash 4-5 g, fat 2-3 g, N 3-3.5 g, P 0.17 g, and K 0.58 g. The high content oftannins (up to 11%) results in low in vitro digestibility of dried foliage of only 35%. There is however, increasing evidence that fresh material has a higher digestibility rate of 60-80%. Such fresh foliage can be fed to livestock in addition to or as a replacement for commercial concentrates; it can compose up to 30% of mixed diets. High levels of tannin also slow down the rate of microbial breakdown of the organic

matter, reducing its value as a source of nitrogenrich green manure. The weight of 1000 seeds is 50-70 g. The wood has an air-dry density of 510-780 kg/m 3 and is strong and easy to saw. The fibre length is 0.66-0.84 mm and the wood contains 49-54% cellulose and 20-23% lignin. The pulp and papermaking properties of calliandra are satisfactory and are comparable to dipterocarps and appropriate for kraft paper manufacture. Calliandra pulp is easily bleached, but wood dimensions are generally small, making handling and chipping difficult. The energy value of the wood is 18 900-19 950 kJ/kg. Description Unarmed shrub or small tree, (1.5-)4-6(-12) m tall, bole up to 30 cm in diameter, bark blackish brown, crown dense. Leaves alternate, bipinnate, rachis 10-19 cm long, without glands, with (3-)6-20 pinnae (2-)4-7(-ll) cm long, each with 19-60 pairs of dark green leaflets; leaflets opposite, oblong, 5-8 mm x 1 mm, acute. Inflorescence terminal, composed of few to many umbelliform flower heads aggregated into a spikelike raceme 10-30 cm long; flower actinomorphic, showy; calyx 2 mm long; corolla 5-6 mm long, pale green; stamens numerous, 4-6 cm long, united at

Calliandra calothyrsus Meisner - 1, flowering branch; 2,peduncle with pods.

CALLIANDRA

base, purplish red. Fruit a pod, linear-oblong and slightly tapering from top to base, flattened, 7-11 cm x 1.0-1.3 cm, margins thickened and raised, sometimes finely pubescent, dehiscing elastically from the apex, 3-15-seeded. Seed ellipsoid, flattened, 5-7 mm long, dark brown mottled. Growth and development Early growth is rapid, on good soil seedlings can reach 2.5-3.5 m in height in 6 months and 3-5 m in 1 year. Calliandra reached 6.0 m in height and 5.8 cm in diameter in 2 years in the Philippines. Roots develop quickly and may reach 1.5-2 m depth in 4-5month-old plants. It forms both superficial and deep penetrating roots. It easily forms root nodules in association with Rhizobium in which nitrogen is fixed. In its natural area of distribution C. calothyrsus flowers predominantly at the end of the rainy season and at the beginning of the dry season, but in Java it flowers throughout the year. Flowering may start in the first year, but good fruit set starts in the second year. Protandrous flowering and the difference in length between the stamens and style indicate outcrossing; the species has a low tolerance of selfing. Pollination is by insects and bats and fruits ripen 3 months after anthesis. Normally, relatively small quantities of seed are produced each year; most seed is produced during the dry season. In areas where pollinators are not in abundance, seed production is very poor as observed in tropical Africa. The presence of numerous thrips can also cause flower abortion and low seed production. In humid climates the tree is evergreen, but in areas with a long dry season it is semi-deciduous. During severe drought trees die back, but generally recover when the rains return. Around the age of 12 years the stem turns brittle, but vigorous new sprouts are readily formed. After pollarding a tree coppices vigorously and annual coppicing may be carried out for 10years or more. Other botanical information Calliandra Benth. comprises about 130 species of shrubs and small trees of tropical and warm temperate regions, some of which are widely cultivated as ornamentals. C. acapulcensis, which occurs in an area geographically separated from the main distribution of C. calothyrsus, has long been considered a separate species. Because the differences between these two taxa are only slight, it is now considered a subspecies occurring in the northern range of C.calothyrsus. Due to the morphological similarity of C. calothyrsus to C. grandiflora (L'Hér.) Benth. and C. houstoniana (Miller) Standley, and the occurrence of hybrids between

the latter two species, there is some confusion about species delimitation. The white-flowered C. tetragona Benth. from Guatemala was also introduced into Java at the same time as C. calothyrsus. Because of its slower growth however, C. tetragona became less popular for plantations. Ecology In its native habitat, C. calothyrsus grows at 0-1300(-1850) m altitude in areas with an average annual precipitation of 700-3000 mm. It is not drought tolerant, but can withstand dry periods of (l-)2-6(-7) months with a rainfall of less than 50 mm. Waterlogging for 2 weeks or longer will kill the tree. In Java it is grown up to 1500 m altitude, but grows best between 250-800 m in areas with 2000-4000 mm annual rainfall and a dry period of 3-6 months. The plants require a mean annual temperature of (20-)2228°C, with mean maximum temperature range in the hottest month of 24-30°C and mean minimum temperature range in the coldest month of 18-24°C. C. calothyrsus is an aggressive colonizer due to its early flowering and seed set, but can be outcompeted in later successional stages by other species. It often invades areas with continual disturbance such as roadsides, river banks and shifting cultivation plots. It grows on a variety of soil types, mainly cambisols, acrisols and nitosols with soil conditions ranging from fertile to relatively infertile, and from acidic to mildly alkaline. It can also be found on andosols in volcanic deposits, shallow or eroded metamorphic sandy clays or recent alluvial deposits. In Indonesia it prefers light soils and slightly acid conditions; best growth is observed on acid soils of volcanic origin. It tolerates acid soils of poor fertility, but growth decreases on compacted soils and trees are not tolerant of a lack of oxygen. Propagation and planting Calliandra is generally propagated from seed, either by direct seeding or by raising seedlings in the nursery. Seed germinates without pretreatment, but acid scarification or hot water treatment followed by soaking in the cooling water for 24 hours may improve the germination rate. The seed, however, is more heat sensitive than those of other legume trees and therefore hot water treatment should be applied cautiously. Seeds retain their viability for at least 2-3 years if stored at 4°C in sealed containers; viability drops from 75%to 60% when stored at room temperature for one year. Direct sowing in the field can be done in planting holes (5 seeds/hole) in furrows or by broadcasting

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on ploughed or burned lands. Aerial sowing has proved satisfactory in Java. Potted plants are transplanted when they are 20-50 cm tall and have a root-collar of 0.5-1 cm. Stumps may be taken from plants approximately 1 m tall by cutting the stem back to 30 cm and the roots to 20 cm. Vegetative propagation by cuttings is also possible, but use of large cuttings has not proved very successful. Two-node cuttings taken from young coppice shoots and treated with indole butyric acid (IBA) will root in about 14 days. Seedlings usually nodulate with native rhizobia and inoculation is only required in new areas. In Indonesia plants have been inoculated using Rhizobium strains CB 756 and CB 3171. Effective mycorrhizal associations may be slow to develop, resulting in poor early growth. However, once an effective mycorrhizal association has formed, growth is vigorous. Areas to be planted are cleared completely. Spacing varies according to purpose. For firewood, planting distances applied are 1 m x 1-3 m; in alley cropping a spacing of25-50 cm in contour rows and generally 4-6 m between the rows is used. For optimal leaf production in fodder banks, stands of up to 40 000 trees per ha (spacing 0.5 m x 0.5 m) can be used. Husbandry Because seedlings grow quickly, no special plantation management is needed, except for weeding in the first year. On infertile soils fertilizer will improve early growth, but calliandra is less responsive to fertilizer than other tree legumes. In alley-cropping systems, calliandra should be pruned in cycles of up to 4 months to limit shade on associated crops. In East Java the productivity of sugar cane and maize could be maintained in a rotation of 4 years of calliandra, followed by sugar cane for 4 years and maize for 2 years, although both sugar cane and maize require large amounts of nitrogen. In Western Samoa, however, alley cropping C. calothyrsus for 4 years with an annual dry matter yield of 7-13 t/ha could not sustain yields ofthe companion crop taro. At present, no specific management practices can be recommended for obtaining optimal wood, fodder or biomass production from C. calothyrsus and little is known about this species' potential to be combined with fodder grasses or other tree species in intensive systems. As C. calothyrsus is a pioneer species, growing in the early stages of a succession, it lacks the ability to compete in later successional stages; therefore mixed plantations with taller trees and dense crowns are not recommended.

Diseases and pests No serious diseases or pests are recorded in Indonesia, but in the Philippines a stem-borer (Callimetopus sp.) causes damage to branches, without causing tree mortality, and Leucopholis irrorata attacks leaves, causing damage in trees planted as ornamentals. In Kenya, a rose flower beetle (Pachnoda ephippiata) has caused floral abortion and poor seed production to such an extent that the insect might limit the use ofC. calothyrsus. Harvesting Harvesting for firewood can start after the first year, and can be followed by annual coppice cuts at the end of the dry season. Fodder can be harvested in cutting cycles of 6 weeks to 6 months. A cycle of 12 weeks proved satisfactory in a fodder production trial in South Sulawesi. To enhance growth, cutting should be carried out at 20-50 cm above the ground. If plants are coppiced too low or during too wet periods, stumps are liable to fungal attack. Yield On moderately fertile soils in Java, first harvests produced 5-20 m 3 /ha per year of fuelwood. On favourable sites on volcanic deposits, annual coppice harvests continued for 10-20 years with an annual yield of 35-65 m 3 /ha. For the Philippines the mean annual volume increment was 25.2 m 3 /ha on a fertile site during the first 2 years. In plantations in Indonesia annual dry fodder yield is 7-10 t/ha. In a trial in South Sulawesi up to 22 t/ha of leaves and up to 22 t/ha of wood were obtained with a tree density of40 000/ha and a cutting cycle of 12 weeks. In Western Samoa an annual yield of 46.2 t/ha was achieved in an alleycropping system when cut at an interval of 6 weeks during the first 1.5 years. When grown in fences, fodder dry matter yields of 1.8-3.2 t per km of fence in 10 months have been obtained. In Western Samoa alleys 4 m wide gave an annual dry matter yield over 4 years of approximately 10 t/ha. Calliandra will often outyield other legume trees on infertile soils, but the yields tend to be similar on more fertile, less acidic soils. Genetic resources A collection of C. calothyrsus germplasm covering 40 sites from 7 countries in Central America is maintained by the Centro Agronómico Tropical de Investigation y Ensenanza (CATIE) in Turrialba, Costa Rica and the Oxford Forestry Institute in the United Kingdom. It is assumed that the introduction of material of C. calothyrsus into Indonesia originated from only two germplasm sources from Guatemala. Therefore, genetic variation in the Indonesian material is very limited. Breeding The large morphological variation

CALLIANDRA

and wide ecological amplitude of calliandra suggest that significant genetic variation will exist between different geographic areas. Iso-enzyme research has shown the existence of 3 groups of provenances. Although genetic improvement of calliandra is still in its infancy, results of some early provenance testing show clear provenance x site interactions, e.g. for drought tolerance. However, no differences have been detected between provenances for wood density, energy value, or ash content. It appears that the seed originally introduced into Indonesia was derived from a fastgrowing, less branching, taller ecotype. All existing plantations in Indonesia are derived from this introduction. As seed production is early and abundant, the proposed strategy for future breeding activities is to start an 'open-pollinated' programme with careful progeny testing and heavy thinning before each seed harvest for the next generation. Prospects C. calothyrsus is a versatile plant used for various auxiliary applications. It has become popular because its high-quality, small-sized fuelwood can be readily produced in annual coppice rotations. Calliandra can also be used in different farming and in a number of agroforestry applications. It grows under a wide range of soil fertility conditions and is often outstanding on infertile sites. It is used extensively for reclamation of bare and degraded lands, including Imperata grasslands. Special attention has been given to its use as an alternative to Leucaena leucocephala (Lamk) de Wit on acid soils or areas infested with leucaena psyllid. Due to its high tannin content the microbial decomposition of calliandra green manure is slower than that of leucaena, resulting in slower nitrogen release. Its high production potential and high protein content make it a promising fodder crop to supplement low-quality forages. It has, for example, potential for use as a high protein feed for fish, rabbits and poultry. However, also due to the high tannin content, the palatability ofcalliandra is less than that ofLeucaena leucocephala or Gliricidia septum (Jacq.) Kunth ex Walp. Further studies are needed to ascertain its full potential as a green manure and as a fodder crop, with emphasis on its ability to improve soil fertility, on its nutritive value and potential for direct grazing. Care must be taken that this hardy plant does not become a weed. Literature 111 Evans, D.O., 1996. International Workshop on the genus Calliandra. Proceedings of a workshop held January 23-27, 1996, in Bogor, Indonesia. Forest, Farm, and Community Tree

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Research Reports, Special issue. Winrock International, Morrilton, Arkansas, United States. 268 pp. 121 Gichuru, M.P. &Kang, B.T., 1989. Calliandra calothyrsus Meissn. in an alley cropping system with sequentially cropped maize and cowpea in southwestern Nigeria. Agroforestry Systems 9(3): 191-203. 131Gutteridge, R.C., 1992. Evaluation of the leaf of a range of tree legumes as a source of nitrogen for crop growth. Experimental Agriculture 28: 195-202. 141 Hernandez, H.M., 1991. Taxonomia, distribucion, geografica y biologica reproductiva de Calliandra calothyrsus (Leguminosae, Mimosoideae), una especie con potential agroforestal [Taxonomy, geographic distribution and reproductive biology of Calliandra calothyrsus (Leguminosae, Mimosoideae), a species with agroforestry potential]. Anales del Institute de Biologia de la Universidad Autonoma de Mexico, serie Botanica 62: 121-132. I5l Macqueen, D.J., 1992. Calliandra calothyrsus: Implications of plant taxonomy, ecology and biology for seed collection. Commonwealth Forestry Review 71(1): 20-34. 161Matheson, A.C., 1990. Breeding strategies for MPTs, Calliandra at CATIE. In: Glover N. & Adams, N. (Editors): Tree improvement of multipurpose species. Forestry/Fuelwood Research and Development (F/FRED) Project, Winrock International, Arlington &Nitrogen Fixing Tree Association, Waimanalo, United States, Multipurpose tree species network Technical Series No 2. p. 87. 171 National Academy of Sciences, 1983. Calliandra, a versatile small tree from the humid tropics. National Academy Press, Washington, D.C., United States. 52 pp. I8l Palmer, B., Macqueen, D.J. & Gutteridge, R.C., 1994. Calliandra calothyrsus - a multipurpose tree legume for humid locations. In: Gutteridge, R.C. & Shelton, H.M. (Editors): Forage tree legumes in tropical agriculture. CAB International, Wallingford, United Kingdom, pp. 65-74. I9l Rosecrance, R.C, Rogers, S. & Tofinga, M., 1992. Effects of alley cropped Calliandra calothyrsus and Gliricidia sepium hedges on weed growth, soil properties, and taro yields in Western Samoa. Agroforestry Systems 19: 57-66. HOIVerhoef, L., 1941.Voorlopige resultaten met enige uit tropisch Amerika ingevoerde Leguminosae [Preliminary results with some Leguminosae introduced from tropical America]. Tectona 34(10): 711-736. K.F. Wiersum &I.K. Rika

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Calopogonium m u c u n o i d e s Desv. Ann. Sei. Nat. Sér. 1, 9:423 (1826). LEGUMINOSAE - PAPILIONOIDEAE

2« =36 Vernacular n a m e s Calopo (En). Indonesia: kacang asu (Javanese), kalopogonium (Indonesian). Philippines: santing (Sulu), karaparapak sara naw (Mar.). Thailand: thua-khalapo. Origin and geographic distribution Calopo is indigenous to tropical America and the West Indies. It was introduced into tropical Africa and Asia in the early 1900s and to Australia in the 1930s. Calopo was taken into use as a green manure and cover crop in Sumatra in 1922 and soon thereafter in the rubber and sisal plantations of the central and eastern parts of Java. It was then brought to Malaysia as a cover crop for rubber. Calopo became naturalized in Indonesia and Malaysia, and has spread to most humid tropical areas ofthe world. U s e s Calopo is well recognized as being a valuable pioneer legume to protect the soil surface, reduce soil temperature, fix atmospheric nitrogen, improve soil fertility and control the growth of weeds. It is an important cover crop for plantation crops, especially rubber and oil palm, where it is often grown in a mixture with centro (Centrosema pubescens Benth.) and tropical kudzu (Pueraria phaseoloides (Roxb.) Benth.). In Africa this mixture has been tested in young forest plantations, where it reduced the cost of weeding. Calopo is also used as a green manure for soil improvement. It is grown as a forage, used especially during the latter part ofthe dry season. Properties Although calopo is a widely used green manure crop, little is known about its chemical composition. A chemical analysis of stems and leaves of plants grown in pots in Malaysia indicated per 100 g dry matter: N 3.8 g, P 0.24 g, K 2.0 g, Ca 1.0 g, and Mg 0.25 g. Nitrogen percentages of 2.6-3.8% have been recorded, but lower values should be anticipated in older, stemmy material. Calopo forage is not very palatable to cattle because taste and smell limit the intake, but animals are forced to eat it during the dry season when little green fodder is available. Its low palatibility, which is usually ascribed to the abundance ofhairs on the stems and leaves, contributes to its persistence in mixed swards. The weight of 1000 seeds is 13-15 g. Description A vigorous, creeping, twining or trailing herb, up to several m long, forming a tangled mass of foliage 30-50 cm deep, with densely

Calopogonium mucunoides Desv. - 1, flowering branch; 2, fruiting branch. pilose stems with long spreading ferruginous hairs. Leaves trifoliolate, petiole up to 16 cm long, pilose; leaflets elliptical, ovate or rhomboid-ovate, (1.5-)4-10(-15) cm x (l-)2-5(-9) cm, the laterals oblique, adpressed pilose or pubescent on both surfaces. Inflorescence a slender raceme, up to 20 cm long, peduncle 0-17 cm long, ferruginous pilose; flowers in fascicles of 2-6, blue or purple; calyx campanulate, unequally 5-lobed; corolla with emarginate standard, about 1cm long. Pod linearoblongoid, 2-4 cm x 3.5-5 mm, straight or curved, softly pilose with coarse reddish-brown hairs, impressed between the seeds, 3-8 seeded. Seed compressed squarish, 2-3 mm long, yellowish or reddish-brown. Growth and development Calopo grows rapidly and is able to cover the soil in 3-6 months after sowing and even sooner on newly cleared, fertile land. It forms a dense entangled sward in 4-5 months after sowing, but the plants are shortlived and may only persist for 1-2 years. When grown as a cover crop in plantation crops in a mixture with tropical kudzu and centro, calopo is the

CALOPOGONIUM

first to become established but also the first to be shaded out. Long-term persistence is through recruitment of new plants from seedlings. The root system is dense and rather shallow, its deepest roots reaching a depth of about 50 cm. Flowering in calopo is initiated by short days. It is self-pollinated and seeds freely. Other botanical information Although widely grown for decades, no improved cultivars of calopo are known to exist. The name 'tortilla' is used to indicate seed of calopo sometimes harvested from naturalized stands in the Adelaide River area of the Northern Territory (Australia). It was at one time thought to have been a long-term locally adapted ecotype, but it is now believed to have come to the area as a contaminant in tropical kudzu seed from Queensland which had been sown in the late 1960s at the Tortilla Flats Research Farm. 'Tortilla' is likely to be similar to Queensland commercial material, which is rarely harvested and has never been assigned a cultivar name. Ecology Calopo is grown from sea level to 2000 m altitude, but is best adapted to altitudes 300-1500 m. It is well suited to the hot humid tropics with an annual rainfall exceeding 1250 mm but not tolerant of frost. It is moderately drought-tolerant but may die out if the dry season is prolonged. Vigorous growth occurs on soils of all textures, even those with a low pH(H 2 0) range of 4.5-5. Its self-seeding nature and twining growth habit make calopo well adapted to a range of ecological conditions. When grown for forage it can be used in a mixture of species, provided it does not become too dominant. Calopo is poorly adapted to shade, showing a marked decline in top growth, root growth and nodulation with decreasing light intensities. This may be attributed to the 'non-plasticity' of leaves under shade as compared with other, shade-tolerant plants such as Calopogonium caeruleum (Benth.) Sauv., Centrosema pubescens and Desmodium heterocarpon (L.) DC. subsp. heterocarpon var. ovalifolium (Wallich ex Prain) Rugayah. Under low light intensities (< 20%) calopo leaves are reduced in size by 70% compared with leaves in full sunlight. In contrast, centro and C. caeruleum leaves are reduced by only 10-25%, while leaves of Desmodium heterocarpon subsp. heterocarpon var. ovalifolium are 20% larger under such a low light intensity. Propagation and planting Calopo is usually propagated by seed, sown at 1-3 kg/ha. Seed is normally drilled in rows when sown into new

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plantations or broadcast in stands to be used for forage production. After seed is broadcast, the seed-bed may be rolled to improve establishment. Newly harvested seed usually has more than 75% hard seed. Mechanical scarification, soaking in concentrated sulphuric acid for 30 minutes, or soaking in hot water (75°C) for 3 minutes is recommended to enhance germination. Although calopo stems root at the nodes when in contact with moist soil the establishment of stem cuttings inserted directly into soil is generally poor. Use of pre and post-emergence herbicides or hand weeding promotes the establishment of calopo. As calopo nodulates promiscuously with native rhizobia, seeds are usually not inoculated. If inoculum is applied, then cowpea strains such as the Australian CB 756 are used. When planted as a cover crop in plantations it is usually sown in a mixture with other legumes such as Calopogonium caeruleum, Centrosema pubescens and Pueraria phaseoloides with 1-3 kg/ha of calopo in a total mixture of 10-15 kg/ha of legume seed. When sown for forage production, calopo has been successfully used in mixtures with stoloniferous grasses, such as molasses grass (Melinis minutiflora Beauv.) and Rhodes grass (Chloris gayana Kunth), and with tussock grasses such as setaria (Setaria sphacelata (Schumacher) Stapf & Hubbard ex M.B. Moss). Good results have been obtained from oversowing it into existing stands of pangola grass (Digitaria eriantha Steud.) which have been harrowed. Husbandry Calopo grows vigorously, shedding a large amount of leaf litter onto the soil which smothers most weeds. Fertilizing acidic soils with ground dolomite and Mo increases yields. Application of P usually increases leaf size. The effect of calopo and associated legumes in improving soil fertility may last for 14-16 years. In an experiment in Malang, Indonesia, a green manure crop of calopo grown for 3 months contained about 65 kg/ha nitrogen in its leaves, shoots and roots. It was followed by a maize crop, which yielded 2.4 t/ha of grain, while a second maize crop following a well-fertilized maize crop had a grain yield of 1.4 t/ha. However, maize following Mucuna pruriens (L.) DC. cv. group Utilis or Crotalaria juncea L. gave significantly higher yields. If calopo is grazed it is advisable to use rotational grazing with rest periods of 8-12 weeks if calopo growth is erect rather than prostrate. Regular slashing is needed when calopo is planted as cover crop in young oil palm and rubber plantations, to prevent the cover from overgrowing the trees. Diseases and pests Calopo is susceptible to

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viruses in Costa Rica, Guatemala and Panama. Beetles and leaf-eating caterpillars have been observed on calopo in Malaysia, but they have not been a serious problem. Harvesting Whether grazed or cut and fed, calopo is often refused by cattle although they eat it less reluctantly during the dry season. It is usually cut by hand and is seldom conserved as hay or silage. Yield When pods are mature, peak dry matter yields of up to 14 t/ha can be obtained in a single cut. Lower yields of4-6 t/ha per year are obtained when calopo is cut every 9-12 weeks. Seed yields of200-300 kg/ha have been recorded. Genetic resources Collections of calopo are held at the Centro Internacional de Agricultura Tropical (CIAT, Colombia) and the Australian Tropical Forage Genetic Resource Centre (ATFGRC, Australia). Breeding There are no known breeding programmes on calopo. Prospects Being one of the components of a widely adopted mixture of cover crops, calopo is likely to remain important in plantation agriculture. Its value as a green manure crop in intercropping systems and in rotations with annual crops still needs confirmation. Low palatability may explain why interest in calopo as a forage plant has faded during the last decade. However, this low palatability and resulting persistence may open up opportunities for incorporating calopo into forage systems as a way ofimproving soil fertility and the growth rate and quality of pastures. Literature 111 Bogdan, A.V., 1977.Tropical pasture and fodder plants. Longman, London, United Kingdom, pp. 328-329. I2l Bunting, B. & Milsum, J.N., 1928. Cover crops and green manures. The Malayan Agricultural Journal 16: 256-280. 131 Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 37-39. I4l Hairiah, K. & van Noordwijk, M., 1989. Root distribution of leguminous cover crops in the humid tropics and effects on a subsequent maize crop. In: van der Heide, J. (Editor): Nutrient management for food crop production in tropical farming systems. Institute for Soil Fertility (IB) Haren &Universitas Brawijaya, Malang, Indonesia, pp. 157-169. 151 Humphreys, L.R., 1980. Aguide to better pastures for the tropics and sub-tropics. 4th ed. Wright, Stephenson & Co., Silverwater, Australia, p. 52. 161 McWeeney, C S . &Wesley-Smith, R.N., 1986. Factors limiting the intake by sheep oftropical legume Calopogonium mucunoides. Australian Journal of Experi-

mental Agriculture 26: 259-264. I7l Skerman, P.J., Cameron, D.G. & Riveros, F., 1988. Tropical forage legumes. 2nd Edition. FAO Plant Production and Protection Series No 2. Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 224-228. 181Wong, C.C., 1990. Mineral composition and nutritive value of tropical forage legumes as affected by shade. MARDI Research Journal 18: 135-143. I9l Yates Seeds, 1987. Better pastures for the tropics. 2nd ed. Yates Seeds, Toowoomba, Australia, pp. 40-41. llOl Yost, R. & Evans, D., 1986. Green manure and legume covers in the tropics. Research Series 055. College of Tropical Agriculture and Human Resources, University ofHawaii, Honolulu, United States, p. 14. Chen Chin Peng &A. Aminah

C a s u a r i n a e q u i s e t i f o l i a L. Amoen. Acad. 4: 143 (1759). CASUARINACEAE

2n = 18,(20) Synonyms Casuarina litorea L. (1759), C. equisetifolia J.R. &G. Forster (1776). Vernacular n a m e s Coast she-oak, ironwood, whistling pine (En). Beach she-oak (Am). Filao (Fr). Indonesia: cemara laut, eru. Malaysia: ru laut. Papua New Guinea: yar. Philippines: Australian pine, agoho. Burma (Myanmar): tin-yu. Cambodia: snga:w. Laos: pè:k namz, son th'ale:. Thailand: son-thale (general). Vietnam: c[aa]y phi lao. Origin and geographic distribution C. equisetifolia has the widest natural distribution of all Casuarina species, occurring naturally along the tropical coastlines from northern Queensland and the Northern Territory in Australia, throughout the whole Malesian region to the Kra Isthmus (Thailand). To the east its natural range extends throughout Melanesia and Polynesia. It is doubtfully indigenous to the Mekong Delta in Vietnam and to Burma (Myanmar) and possibly also to Madagascar. It has also been introduced into a large number of countries and is now a common feature of the coastal landscape of most tropical and warm subtropical countries, where it is often naturalized. U s e s The most common uses of C. equisetifolia are for coastal sand dune stabilization, shelterbelts, land reclamation and erosion control. It is a popular agroforestry tree in coastal and saline areas. In Sarawak it is protected because of its importance in controlling coastal erosion. Many ar-

CASUARINA

eas of occurrence are susceptible to tropical cyclones or typhoons and C. equisetifolia's general tolerance to strong winds has encouraged its use in protective plantings. A 3000 km long belt along the coast of southern China is planted to C. equisetifolia for this purpose. The wood is highly regarded as a fuel. It burns even when green and produces high quality charcoal. The small branch litter is often collected for domestic fuel and is sometimes used to fuel pottery and brick kilns. Poles are popular as masts for fishing boats, piles, posts and tool handles. Sawn timber is only used for small items like roofing shingles. The wood is used to produce paper pulp using neutral sulphate and semi-chemical processes and as raw material for rayon fibres. In Egypt it is used to make chipboard. The bark has been used for tanning and is still occasionally used by amateur tanners. Medicinal use is made of the roots to treat dysentery, diarrhoea and stomach ache. In West Malaysia, a decoction of the twigs is used for treating swellings and the powdered bark is used for treating facial pimples. Production and international trade No statistics are available on production and trade. Properties The bark of C. equisetifolia is astringent and contains 6-18% tannins. Tests of the chemical composition of the branchlets in Puerto Rico gave per 100 g dry matter: N 1.56 g, P 0.16 g, K 0.48 g, Ca 1.23 g, Mg 0.23 g, Na 3.28 g. The wood is hard and heavy with an air-dry density of 900-1000 kg/m 3 , sapwood being slightly heavier than heartwood. Green logs have a moisture content of 40-60%. The energy value of the wood is 24 000 kJ/kg and that of the charcoal exceeds 33 500 kJ/kg. The wood produces little ash and burns even when green. On sawn timber the rays are prominent on radial faces. The wood tends to warp and crack on drying. The weight of 1000 seeds is 1.4-3.3g. Description Monoecious tree with a finely branched crown, 6-35 m tall, with trunk diameter up to 50 cm; bark light greyish-brown, smooth on young trunks, rough, thick, and furrowed on older trees; inner bark reddish and astringent; branchlets deciduous, drooping, needle-like, terete but with prominent angular ribs, 23-38 cm x 0.5-1 mm, greyish-green, articles 5-8 mm long, glabrous to densely pubescent. Leaves reduced to minute teeth, in whorls of 7-8 per node. Male flowers in a terminal, simple, elongated spike, 7-40 mm long, borne in whorls with 7.0-11.5 whorls per cm of spike. Female inflorescence on lateral woody

Casuarina equisetifolia L. - 1, habit ofyoung tree; 2, habit of flowering branch; 3, part of branchlet; 4, branch with male and female inflorescence; 5, infructescence (cone); 6,fruit (samara). branches, cylindrical, cone-shaped or globose, 1024 mm long, 9-13 mm in diameter; bracteoles acute, more or less protruding from the surface of the cone. Fruit a samara, 6-8 mm long, 1-seeded, dull brown. Seed with epigeal germination. Growth and development C. equisetifolia has a life span of 40-50 years and displays fast early growth. Under favourable conditions early growth in height may exceed 3 m per year. At 10 years a height exceeding 10 m and a diameter of 20 cm may be reached. Branching in Casuarinaceae is dimorphic. Most prominent are the green needle-twigs that are functional leaves with a limited life and determinate growth. With age they turn brown and are shed. The other type of branch is normal, woody, with indeterminate growth. Tree form in wild populations is very variable, from crooked low-branching trees on exposed seashores to straight-stemmed forest trees with a narrowly conical crown in more sheltered situations and in plantations. C. equisetifolia coppices

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only to a limited extent and only when cut young (3-4 years). Although trees in natural stands are mostly monoecious, many introduced populations are dioecious. Pollination is by wind. Female cones mature about 18-20 weeks after flowering, and open shortly thereafter, releasing the small winged fruitlets. C. equisetifolia forms large, long-lived, woody root nodules with several strains of the actinorhizal symbiont, Frankia, which enables it to fix atmospheric nitrogen. These root nodules can be prolific. Extrapolations from experimental data indicate that 90 kg/ha of atmospheric nitrogen can be fixed annually at a planting density of 2000 trees per ha. Uptake of other plant nutrients is enhanced by the presence of proteoid roots and associations with ectomycorrhizal and endomycorrhizal fungi. As in other actinorhizal plants, endomycorrhizal (VAM)infection occurs easily. Other botanical information Linnaeus's publication of C. equisetifolia consists only of a name and a reference to a drawing by Rumphius. Unfortunately, the name contains a printing error (equisefolia) and many sources therefore cite J.R. & G. Forster as the original authors. Correction of the typographical error is allowed, however. In C. equisetifolia two subspecies have been distinguished: subsp. equisetifolia is most common and most widely distributed; subsp. incana (Benth.) L.A.S. Johnson occurs exclusively along the coast of Queensland and northern New South Wales and on Vanuatu. It is a 6-12 m tall tree with densely pubescent immature branchlets with sometimes flat and wrinkled ribs. Ecology C. equisetifolia is commonly confined to a narrow strip adjacent to sandy coasts, usually from sea level to 100 m altitude, but recorded to 600 m in Hawaii and 800 m in the Philippines. It is planted up to 1200 m altitude. It is found on sand dunes, in sands alongside estuaries behind foredunes and gentle slopes near the sea. It may be found at the leading edge of dune vegetation, subjected to salt spray and inundation with sea water at extremely high tides and where it may be the only woody species, growing over a ground cover of dune grasses and salt-tolerant broadleaved herbs. It may also be part of the richer Indo-Pacific beach flora, in which it grows in association with Barringtonia asiatica (L.) Kurz, Calophyllum inophyllum L., Heritiera littoralis Aiton, Hibiscus tiliaceus L., Thespesia populnea Sol. ex Correa and Pandanus species. It requires much light. Seedlings do not grow in the shade of uni-

form C. equisetifolia stands and such stands are gradually replaced by mixed forest, with a single file ofC. equisetifolia trees along the sea front. The climate in its natural range is semi-arid to sub-humid and frost-free. Rainfall varies from 700-2000(-3500) mm per year. In most regions there is a distinct dry period of 4-6(-8) months, although this seasonality decreases towards the equator in South-East Asia and in the southern parts of its range in Australia. C. equisetifolia is intolerant of prolonged waterlogging. It can grow in semi-arid climates with annual rainfall of less than 350 mm where sea spray and high air humidity supplement rainfall. Mean minimum temperature of the coldest month ranges from 7°C-20°C, mean maximum temperature of the hottest month from 20°C-35°C. Soils are invariably well-drained and rather coarse-textured, principally sands and sandy loams. The tree tolerates saline, calcareous and slightly alkaline soils and is very well adapted to soils oflow fertility. Propagation and planting Propagation is mainly by seed, although cuttings are increasingly used. Seed requires no pretreatment. Germination takes up to two weeks. In Thailand and India cuttings are made from small branchlets 10-15 cm long and 2 mm in diameter. Rooting is enhanced through use of the hormones indole-3-butyric acid (IBA) or indole-3-acetic acid (IAA). In southern China cuttings are taken from branchlets of 5 cm long and 1 mm in diameter and soaked in a solution of naphthalene-1-acetic acid (NAA) before being placed in polythene bags. Inoculation of the seedlings with a pure culture of effective strains ofFrankia is recommended when C.equisetifolia is introduced to a new area. This is done by applying a water suspension of the inoculant to the seedlings. Applying a solution of crushed nodules works less well. The availability ofmycorrhizal fungi can be assured by adding soil collected from established stands to the potting medium. Early growth can be doubled as a response to inoculation. Plantations can be established using containerized seedlings, bare-root seedlings or rooted cuttings. Plants are typically suitable for planting out when 25-30 cm tall, though in the desert climate of Egypt smaller seedlings are preferred. A density of 2500 plants per ha is commonly used, but some private farmers plant up to 8000-10 000 plants per ha. Young trees compete poorly with weeds, so weeding is important for 2 years after planting.

CASUARINA

Husbandry C.equisetifolia is considered to be a poor self pruner. Pruning in plantations is necessary up to 2 m, to keep plantations accessible for general maintenance. Pruning may, however, allow infection with fungal pathogens, especially Trichosporium vesiculosum. C. equisetifolia is not fire-resistant and protection is necessary, even against light fires. Leaf litter from plantations is frequently removed for fuel; this depletes the soil's reserves ofphosphorus and potassium. Diseases and pests C. equisetifolia is only rarely attacked by diseases and pests except when grown under unfavourable conditions. The most serious disease threatening C. equisetifolia plantations is blister blight caused by the fungus Trichosporium vesiculosum. Infected trees exhibit symptoms of foliar wilt and cracking of the bark, where blisters develop enclosing a black powdery mass of spores. Bacterial wilt disease caused by Pseudomonas solanacearum, characterized by yellowing of the foliage followed by wilting and death, has been reported in China and India. Other potentially serious diseases include stem canker and dieback caused by Phomopsis casuarinae and pink disease (Corticium salmonicolor). In the nursery and in newly-established plantations, seedlings are sometimes attacked by termites, crickets or rodents. Young trees may be seriously damaged by browsing animals. Harvesting Rotation periods vary from 6-15 years when harvesting for fuelwood. Yield On favourable sites, C. equisetifolia can reach an annual increment of 15 m 3 /ha at 10 years. In India, plantations using 1-2 m x 1-2 m spacing on 6-15 year rotations yield 50-200 t of wood per ha. Dry weight of stems, branches and twigs per tree ranges from 15to 25 kg at 3years of age, depending on site quality. Up to 4 t/ha of litter and twigs may be harvested for fuel. Genetic resources The Australian Tree Seed Centre of the Division of Forestry and Forest Products of the Commonwealth Scientific and Industrial Research Organization (CSIRO) has a collection of seed material collected from 65 sites in 21 countries. International trials to evaluate this material are under way on about 30 sites in 20 countries and are being coordinated by the Australian Tree Seed Centre. The large phenotypic variation displayed between populations can be exploited for tree improvement. The effectiveness of different Frankia strains varies greatly. Frankia collections are maintained by the Office de la Recherche Scientifique et Technique d'Outre-Mer (ORSTOM) in France, the CSIRO Divi-

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sion of Soils in Townsville, Australia and at the School of Forestry at Yale University, Cambridge, United States. Breeding Considerable improvements in growth following conventional plant breeding and screening of élite trees followed by vegetative propagation are anticipated. Prospects C. equisetifolia will remain of considerable importance for agroforestry and reclamation of unstable coastal ecosystems in tropical countries. Improvement by breeding and concurrent screening of Frankia and mycorrhiza strains for effectiveness will receive priority. Literature 111Dommergues, Y., 1990. C. equisetifolia: An old-timer with a new future. Nitrogen Fixing Tree Association. NFT Highlights 90-02. 2 pp. 12! El-Lakany, M.H., Turnbull, J.W. & Brewbaker, J.L. (Editors), 1990: Advances in Casuarina research and utilisation. Proceedings of the Second International Casuarina Workshop, January 15-20, 1990, Cairo. Desert Development Centre, American University in Cairo, Cairo, Egypt. 241 pp. 131Midgley, S.J., Turnbull, J.W. & Johnston, R.D. (Editors), 1983. Casuarina ecology, management and utilization. Proceedings of an International Workshop, 17-21August 1981, Canberra, Australia. Commonwealth Scientific and Industrial Research Organization (CSIRO), Melbourne, Australia. 286 pp. I4l Pinyopusarerk, K., 1993. Casuarina: an annotated bibliography of C. equisetifolia, C. junghuhniana and C. oligodon. International Centre for Research in Agroforestry (ICRAF), Nairobi, Kenya. 298 pp. I5l Pinyopusarerk, K , Turnbull, J.W. & Midgley, S.J. (Editors), 1996. Casuarina research and development. Proceedings of the Third International Casuarina Workshop, 4-7 March, 1996. Da Nang, Vietnam and CSIRO,Australia. 161 Wilson, K.L. & Johnson, L.A.S., 1989. Casuarinaceae. Flora of Australia. Vol. 3. Bureau of Flora and Fauna, Australian Government Publishing Service, Canberra, Australia, pp. 100-106. S.J. Midgley &R. Sylvester

Casuarina j u n g h u h n i a n a Miquel Plantae junghuhnianae 1:7 (1851). CASUARINACEAE

2ra= 18 Synonyms Casuarina montana Junghuhn ex Miquel (1855). Vernacular n a m e s Red-tipped ru, mountain ru (En). Indonesia: cemara gunung (Indonesian), ad-

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jaob, kasuari (Timor). Thailand: son-pradiphat. Origin and geographic distribution C. junghuhniana is indigenous to Indonesia where it occurs in East Java and the Lesser Sunda Islands (Bali and Nusa Tenggara) from Bali to Timor and Wetar. It has been introduced to Kenya and Tanzania. A male, hybrid plant was introduced into Thailand in about 1900, and its progeny was taken from there to India in the early 1950s. Uses C.junghuhniana is planted widely, especially in Indonesia, to improve soil fertility and rehabilitate degraded soils and as a wind-break. Branches and foliage are burnt and the ash is spread on village gardens in Timor. The wood is highly suitable for firewood and charcoal production. In Thailand, it is a popular source of construction piles and for fish traps. In Kenya and Tanzania farmers plant C.junghuhniana around fields for poles and firewood and as a live fence. The wood is a suitable source of raw material for kraft pulp. It can be used to make hardboard in a mixture with Dipterocarpus spp. Although it is not a fodder, young trees are browsed by animals. P r o d u c t i o n a n d international trade No statistics are available on wood production, international trade and areas planted to C. junghuhniana. Most plantings in Thailand and Kenya are scattered in small plots of a few hectares. Properties Branchlets decompose slowly and provide good mulch. The air-dry density of the wood is 900-1000 kg/m 3 , and that of charcoal is 650 kg/m 3 . The energy value of the charcoal is 34 500 kJ/kg, which is among the highest for firewood species. Average durability of untreated wood is 4.5 years in direct contact with the ground. This can be increased to 15years by treatment with a creosote preservative. The weight of 1000 seeds is 0.6-1.0 g. Description A fast-growing, dioecious tree, 15-25C-35) m tall; trunk diameter 30-50(-65) cm; crown somewhat open. Branching dimorphic with normal woody branches and determinate, deciduous branchlets; deciduous branchlets (switch twigs) numerous, articulate, internodes 10-15 mm long, greyish-green. Leaves reduced to tiny teeth, in whorls of 9-ll(-13). Male inflorescence a cylindrical or slightly clavate spike, 3-8 cm long, borne on the apex of a deciduous branchlet; sheathing bracts hairy outside; lobes 10-11; bracteoles mucronate, 1.7-2.0 mm long; perianth lobes 0.7-1.7 mm long; filament 3.0-3.5 mm long. Female inflorescence in the axil of scale leaves on permanent

Casuarina junghuhniana Miquel - 1, habit of branch with fruits; 2, branch with male inflorescences; 3, detail male inflorescence; 4, female inflorescence; 5, infructescence (cone). shoots, cone-shaped, ellipsoid, truncate, 1-2 cm long, reddish; bracts 18-20-seriate, broadly obtriangular; bracteoles oblong-obovate, rounded or very obtuse, thick, 5-6 mm x 2.5-3.0 mm. Fruit a samara, small, 2-3 mm wide and 4-5 mm long including wing. Seedling with epigeal germination. Growth and development Mature seeds germinate readily without pretreatment. The germination rate is 50-60%, decreasing rapidly unless kept in dry, cool storage. The cotyledons are folded initially, later extending and becoming oblong. Under favourable conditions seedlings attain 25-30 cm in height within 3 months. As the main stem elongates, side branches develop from the upper axils of scale leaves. They are upright, giving the crown a slender, conical shape. Young trees continue to develop a conical crown; with age it tends to flatten. Seedlings can attain 3 m growth in height per year during the first 2-3 years. In plantations with a controlled water regime in Thailand the C.

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junghuhniana hybrid reaches 20 m in height and 15 cm in diameter in 5 years. In Markhanam, Tamil Nadu, India, hybrid trees reach a height of 5 m in 20 months. Shoot growth tends to cease or to be less during the flowering period which coincides with the dry season. Like other Casuarina spp., C. junghuhniana is wind-pollinated. C. junghuhniana fixes atmospheric nitrogen by nodulation with actinomycete bacteria of the genus Frankia. The nodules are woody and perennial and can form large masses in the root system. Mycorrhizal fungi further enhance its adaptability to poor soils. Other botanical information C. junghuhniana is rather variable. In its easternmost area of distribution, 2 forms occur, locally known as black and white casuarina, respectively. C. junghuhniana has coarse and fine branchlet variants. The forms with coarse branchlets may occur on exposed sites and are notable also for their rough, deeply-furrowed corky bark which is unusual for Casuarina spp. C.junghuhniana hybridizes readily with C. equisetifolia L. in cultivation, but not in the wild. The male hybrid introduced to Thailand has good form with straight stem and symmetrical conical crown. It is popular for commercial forestry and as an ornamental. Ecology C. junghuhniana grows naturally on the slopes of volcanoes at altitudes of 1500-3100 m but also at lower altitudes in dry places. In eastern Indonesia, especially on Timor, it occurs from near sea level up to 550 m altitude. Rainfall in the natural habitat is monsoonal, with a well-defined summer maximum and a reported annual range of 700-1500 mm. Mean maximum temperature of the hottest month ranges from 25-28°C, mean minimum temperature ofthe coldest month from 19-22°C. It is drought-tolerant and can survive prolonged waterlogging. Near Bangkok commercial plantations in salt-marsh areas are sometimes inundated with saline water. When trees reach a few metres in height they are fire resistant and sprout readily after being damaged by fire. C. junghuhniana grows on a wide range of soils, from light volcanic and sandy soils to heavy clays. It is tolerant of a wide pH range, from 2.8 in acidic clays to 8.0 in limestone-derived soils. Propagation and planting Propagation is by seed, shoot cuttings or air layering. Seed is sown onto germination beds. Seedlings are pricked out into polythene bags when 3-5 cm tall. For mass propagation, shoot cuttings are more suitable

than air layering. Young shoots 1-2 mm in diameter and 10-15 cm in length are rooted with the help of hormones, either indole-4-butyric acid (IBA), indole-4-acetic acid (IAA) or naphthalene-1acetic acid (NAA).Under 50% shade, rooting takes 3-4 weeks. Inoculation of the seedlings or cuttings with effective strains of Frankia is recommended when C. junghuhniana is introduced to a new area. Some Frankia strains of C.equisetifolia are effective on C. junghuhniana. When C. junghuhniana or C. equisetifolia are already being cultivated in an area, it is usually sufficient to mix topsoil collected from the plantations into the potting media. A spacing of 2 m x 2-3 m is used for commercial plantations for poles. Husbandry Weeding is necessary only during the first few years, after which the trees shed large amounts of branchlets to form a thick and dense mat oflitter that suppresses weeds. C. junghuhniana is a poor self-pruner, and produces strong root suckers. Pruning in plantations up to a height of 2.0-2.5 m is often necessary to make the plantations more accessible for general maintenance. Trees respond well to coppicing and pollarding. Diseases and pests A number of diseases are found associated with C. junghuhniana. Damping-off of seedlings in nurseries is caused by various fungi (Phytophthora sp., Pythium sp., Fusarium sp., Sclerotium sp. and Rhizoctonia sp.). Butt and heart rot, caused by Ganoderma applanatum, may infest tree trunks after damage by fire. Schizophyllum commune may cause decay of the sapwood. Green branchlets are attacked by the Acrididae locust Aularches miliaris and insects of the family Lymantriidae. In dry areas subterranean termites can destroy young plants by eating their roots. In Thailand they are controlled by spreading a small quantity of a mixture of equal amounts of lime and salt in the planting hole. Harvesting Plantation-grown trees can be harvested throughout the year. In Thailand a harvesting cycle of 5 years is used for poles and fuelwood planted at a spacing of2m x 2-3 m. Yield In the highlands of Tanzania trees from a woodlot yielded 14.7 m 3 stacked wood at age 4.3 years, and those planted along contour strips in an agroforestry trial produced 180 kg air-dry fuelwood per tree at age 3.5 years. In general, a mean annual increment of 10-15 m 3 /ha is obtainable. Handling after harvest In Thailand felled trees are transformed to poles by removing side

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branches. The length of poles is cut proportionately to the diameter, i.e. 3 m pole length for 7.5 cm diameter, 4 m pole length for 10 cm in diameter. Off-cuts from stems or branches are excellent firewood for the pottery industry. No special handling is required if the products are marketed as poles, piles or firewood. The wood, however, has a tendency to split when sawn. Genetic resources The Australian Tree Seed Centre, Commonwealth Scientific and Industrial Research Organization (CSIRO), Division of Forestry and Forest Products in Canberra has assembled germplasm from throughout the natural distribution ofC.junghuhniana and from derived occurrences in Kenya and Tanzania. The Forestry Seed Centre in Kenya and the National Tree Seed Project in Tanzania collect and conserve seed from locally cultivated trees. Breeding Activities on tree improvement work appear to be limited to a small progeny trial in southern China established with seed mainly from Kenya and Tanzania, and from a small number of trees from Timor. International provenance trials have been established to examine genetic variation. Prospects Due to its fast growth, its nitrogenfixing capacity, its wide adaptability, ease of propagation and excellent fuelwood quality, C. junghuhniana has the potential to be planted for a range of purposes in the semi-arid to humid tropics, under both lowland and highland conditions. Literature 111 Chittachumnonk, P., 1983. Silviculture of Casuarina junghuhniana in Thailand. In: Midgley, S.J., Turnbull, J.W. &Johnston, R.D. (Editors): Casuarina ecology, management and utilization. Proceedings of an International Workshop, 17-21 August, 1981, Canberra, Australia. Commonwealth Scientific and Industrial Research Organization (CSIRO), Melbourne, Australia, pp. 102-106. 2 National Research Council, 1984. Casuarinas: nitrogen-fixing trees for adverse sites. National Academy Press, Washington, D.C., United States. 118 pp. 131Okorio, J., Byenkya, S., Wajja, N. &Peden, D., 1994. Comparative performance of 17 upperstory tree species associated with crops in the highlands of Uganda. Agroforestry Systems 26: 185-203. 141Pinyopusarerk, K. & Boland, D.J., 1990. Casuarina junghuhniana - an Indonesian species of promise for the tropics. In: El-Lakany, M.H., Turnbull, J.W. & Brewbaker, J.L. (Editors): Advances in casuarina research and utilization. Proceedings of the Second International Casuarina Workshop, January 15-20, 1990, Cairo. Desert Development

Center, American University in Cairo, Cairo, Egypt, pp. 202-212. I5l Turnbull, J.W., 1990. Taxonomy and genetic variation in Casuarina. In: ElLakany, M.H., Turnbull, J.W. & Brewbaker, J.L. (Editors): Advances in Casuarina research and utilization. Proceedings ofthe Second International Casuarina Workshop, January 15-20, 1990, Cairo. Desert Development Center, American University in Cairo, Cairo, Egypt, pp. 1-11. K. Pinyopusarerk

Centrosema pubescens Benth. Comm. legum. gen.: 55 (1837). LEGUMINOSAE - PAPILIONOIDEAE

2n = 22 Synonyms Centrosema molle Martius ex Benth. (1837). Vernacular n a m e s Centro, butterfly pea (En). Flor de conchitas (Am). Indonesia: sentro. Philippines: dilang-butiki (Tagalog), lesu-kesu (Subanun). Thailand: thua-lai, thua-sentro. Vietnam: day trung ch[aa]u l[oo]ng. Origin and geographic distribution Originating in South and Central America, centro is now one of the most widely distributed of all legumes in the humid tropics. Centro was introduced to South-East Asia from tropical America in the 19th Century or earlier. It occurs naturalized in lowland Java. Uses In 1922 centro was discovered in a heavily shaded rubber plantation in Central Java, and was quickly adopted as a green manure and ground cover in plantation crops in Java, Sumatra, Peninsular Malaysia and Sri Lanka. Since the 1950s, centro has been widely used as a plantation cover and pasture legume in South-East Asia, the Pacific Islands, the wet tropics of Australia and indeed much ofthe humid tropics worldwide. Properties Centro is an efficient fixer of atmospheric nitrogen, with N concentrations generally ranging from 2.4-2.7(-3.2)%. The amount of nutrients temporarily immobilized in a centro cover can be high. Under intensively managed, well fertilized oil palm on a marine clay soil in Selangor, Malaysia, a centro cover produced 13.3 t/ha dry matter 20 months after planting, of which 5.4 t/ha was living biomass and 7.9 t/ha was litter. The nutrient content of the living biomass was per 100 g dry matter: N 2.51 g, P 0.17 g, K 1.92 g, Mg 0.23 g. Per 100 g dry matter the litter contained: N 3.18 g, P 0.12 g, K 0.36 g, Mg 0.38 g. Under comparable conditions on a sandstone-derived soil in Serdang,

CENTROSEMA

Malaysia, the production 12 months after planting was 4.5 t/ha living biomass and 6.7 t/ha litter, containing per 100 g dry matter of living biomass: N 3.06 g, P 0.51 g, K 2.07 g, Mg 0.14 g and of litter: N 2.34 g, P 0.44 g, K 0.35 g, Mg 0.11 g. Centro is one ofthe most palatable tropical legumes. The weight of 1000 seeds is about 25 g. Description A vigorous, climbing, perennial herb; trailing runners have a tendency to root at the nodes if soil moisture is high, giving it a stoloniferous appearance; roots penetrating deeply; development oftaproot and lateral roots is almost equal, although soil type exerts some influence. Stems leafy, arising from the main runners at 0.5-1.5 m intervals, climbing rather than trailing, slightly hairy, possibly becoming woody when older than 18 months. Leaves trifoliolate; leaflets elliptical, ovate-oblong or ovate-lanceolate, 1-7 cm x 0.5-4.5 cm, rounded at the base, rounded to sharp-acuminate at the apex, dark green, slightly hairy, especially on the lower surface; petiole up to 5.5 cm long, stipules 2-4 mm long, persistent. Flower cleistogamous, large, pale mauve with pur-

Centrosema pubescens branch; 2,pods; 3, seed.

Benth.

- 1,

flowering

93

pie lines in the centre, borne in axillary racemes, 3-5 per raceme, subtended by 2 striate bracteoles; calyx tube campanulate, teeth unequal, 2 upper ones ovate-triangular 1.5-3 mm long; standard rounded, up to 3 cm in diameter, hairy on the outside, bright or pale lilac on either side of a median greenish-yellow band with numerous dark violet stripes or blotches. Pod linear, 4-17 cm x 6-7 mm, flattened, margins prominent, straight or slightly twisted, acuminate, dark brown when ripe, containing up to 20 seeds. Seed shortly oblongoid to squarish with rounded corners, 4-5 mm x 3-4 mm x 2 mm, brownish-black, with mottled darker blotches. Growth and development Centro is notoriously slow to establish and requires good conditions and regular weeding during the establishment period, but when grown in a pure sward it forms a dense, compact cover 35-45 cm deep, 4-8 months after sowing. In mixtures it becomes fully established and vigorous by at least the 2nd year. In ungrazed mixtures with Guinea grass (Panicum maximum Jacq.) it forms an impenetrable vine canopy some 2 m high. In the commonly planted mixture with calopo (Calopogonium mucunoides Desv.) and tropical kudzu (Pueraria phaseoloides (Roxb.) Benth.) centro persists longest under the closing canopy of plantation crops and is comparable in persistence to Calopogonium caeruleum (Benth.) Sauv. In Australia common centro flowers in April and October, with main seed harvesting periods in June-July and November-December. Cultivar 'Belalto' flowers in June and has a main seed harvesting period in early August. Nodulation occurs with a range of rhizobia but optimal growth has been achieved with very few strains. Inoculation with an effective strain of Bradyrhizobium is therefore recommended. Estimates of atmospheric nitrogen fixation range from 120-270 kg/ha per year. Other botanical information Commercially grown forms of C. pubescens represent only a small fraction of its diversity, and any statement on the commercial forms does not necessarily pertain to the species as a whole. Two lines of centro are in commercial use: common centro and cultivar 'Belalto'. 'Belalto' is now identified as C. schiedeanum (comb, ined., syn.: Clitoria schiedeana Schlecht.) rather than as C. pubescens as was listed originally. It was selected by the Queensland Department of Primary Industries as an improvement over common centro because of its superior cool season growth, greater tolerance of pests and diseases, and its stronger

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stoloniferous growth. Its origin is Costa Rica. Ecology Centro is cultivated in the humid tropics up to an altitude of 600(-900) m. It prefers an annual rainfall of 1500 mm or more, but is also tolerant of lower rainfall, having persisted in pastures in Africa receiving an average annual rainfall of 800 mm. Centro tolerates some waterlogging when grazing is lenient and it will survive a dry season of 3-4 months, but is not adapted to prolonged drought. It is intolerant oflow temperatures; growth is noticeably reduced when temperatures fall below 20°C and poor below 15°C. Frost of -3°C causes substantial leaf death, but plants may regrow from sheltered growing points near the ground. Centro is one of the shade-tolerant legumes and can persist under 80% shade. It will grow on a range of soils from sandy loams to clays. Acceptable growth may be obtained on relatively acid soils, provided extractable aluminium is less than 0.2 meq per 100 g soil. The pH range tolerated is about 4.5-8.0, but nodulation is poor towards the extremes of the range, the optimum pH being 5.5-6.0. Although centro is fairly tolerant of high Mn levels in the soil, low-pH-related Mn toxicity has been observed in acid soils, though this can be corrected by liming. Centro combines well with other species in ground covers or mixed pastures under plantation crops. In the humid tropics the preferred legumes for fertile and infertile soils have traditionally been centro and stylo (Stylosanthes guianensis (Aublet) Swartz) respectively. However, when soil mineral deficiencies are corrected and seed is inoculated with an effective Bradyrhizobium, centro has been more productive than stylo on all land classes. Propagation and planting Centro is propagated by seed. Hand-harvested seed has a high proportion of hard seed (up to 60%) and mechanical scarification is required. Seed rate is about 5 kg/ha. Since centro is somewhat slow to establish, careful seed-bed preparation and planting procedures are recommended. However, centro has been successfully sod-seeded directly into a rundown grass pasture, following heavy grazing and low slashing ofthe residual grass. Husbandry When planted as a component of a soil cover in oil palm or rubber plantations, centro will persist for 3-6 years until the tree canopy closes. It contributes considerably to the nitrogen nutrition of trees. In an experiment in Malaysia comparing centro with grasses as cover crop under oil palm, the N levels ofoil palm leaves were about 10% higher with centro than with grasses. Observations in northern Queensland showed that

levels of soil N in regularly grazed, unfertilized mixed pastures of centro and Guinea grass hardly declined over a period of 16 years. Properly fertilized and carefully grazed grass/centro associations have been persistent, productive and competitive against weeds and timber regrowth. In mixtures with grasses, notably Guinea grass, centro tolerates rotational or continuous grazing, but in pure stands it is intolerant of grazing. Under acidic soil conditions, centro is more responsive to Mo, Ca, K and P than tropical kudzu which, in turn, is more responsive than stylo. Centro is more sensitive than stylo to soil P deficiency but is less sensitive to Cu and possibly S deficiencies. Bioassays conducted in Taiwan revealed that banana growth is affected by Phytotoxins from interplanted centro. The phenolic compound p-hydroxybenzoic acid in centro caused a growth inhibition similar to that produced by rhizosphere or plant extracts. Diseases and pests Centro is relatively free of major diseases and pests, although some virus and bacterial diseases have been noted from time to time and seasonal infestations of Cercospora leaf spot and red spider mite {Tetranychus sp.) have been reported. In the humid tropics it is noticeable that the infestation of foliar blight (Rhizoctonia solani) may cause some dieback and that the attack ofladybird beetles (e.g.Epilachna indica) may affect plant growth and even cause complete defoliation. The damage can be severe when centro is grown in a pure sward, especially during the wet season. However, none of these have warranted commercial control measures. Harvesting Centro has persisted for decades as plantation cover or in well-managed grazed associations with grasses, but it has not been very stable in cut-and-carry systems. When used as fodder centro is usually grazed, or it can be cut for stall feeding. It can be selectively overgrazed unless care is taken. Centro is usually consumed fresh but it can be ensiled or dried for hay or pellets. Yield Biomass production of cover crops is rarely measured. Pure stands of centro have produced annual dry matter yields ofup to 12 t/ha. In mixed pastures this is more likely to be about 3-4 t/ha per year. Standing dry matter yield of centro in grazed mixed pastures is unlikely to exceed 1 t/ha. Well managed grass/centro pastures have consistently supported stocking rates of 4 steers (of 250 kg liveweight) in the Malaysian wet tropics, producing about 500 kg/ha of liveweight gain per year. Seed production can reach more than 200 kg/ha.

CHROMOLAENA

Genetic resources Seed ofcentro has been sold for many decades in South-East Asia and other humid tropical areas. Large germplasm collections are held by the Australian Tropical Forage Genetic Resource Centre (ATFGRC, Australia), the Centro Nacional de Recursos Genéticos/Empresa Brasileira de Pesquisa Agropecuâria (CENARGEN/EMBRAPA, Brazil) and the Centro International de Agricultura Tropical (CIAT, Colombia). Breeding Plant breeding programmes have been undertaken and improved cultivars have been released by the Queensland Department of Primary Industries (QDPI) and the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia and CIAT in Colombia. However, the most promising lines are beginning to emerge from plant collections in South and Central America. Prospects Centro will continue to be an important component of cover crop mixtures for plantation crops, although its role as shade-tolerant component has been partly taken over by Calopogonium caeruleum. Centro is also a recommended legume in the 'Three Strata Forage System' in Bali, Indonesia. Except for the humid tropics of Australia and a few areas of Malaysia and the Philippines, the potential of centro as a component of grazed pastures has been largely unrealized. Literature 111 Clements, R.J., Williams, R.J., Grof, B. & Hacker, J.B., 1983. Centrosema. In: Burt, R.L., Rotar, P.P., Walker, J.L. & Silvey, M.W. (Editors): The role of Centrosema, Desmodium, and Stylosanthes in improving tropical pastures. Westview Press, Boulder, Colorado, United States, pp. 69-96. |2| Han, K.J. & Chew, P.S., 1982. Growth and nutrient content of leguminous covers in oil palm plantations in Malaysia. In: Pusharajah, E. & Chew, P.S. (Editors): The oil palm in agriculture in the eighties. Vol. 2. The Incorporated Society of Planters, Kuala Lumpur, Malaysia, pp. 235-251. 131 Nitis, I.M., Lana, K , Suarna, M., Sukanten, W., Putra, S. & Arga, W., 1989. Three strata system for cattle feeds and feeding in dryland farming area in Bali. Final report to the International Development Research Centre, Ottawa, Canada. 252 pp. 141 SchultzeKraft, R. & Clements, R.J. (Editors), 1990. Centrosema: biology, agronomy and utilisation. Centro International de Agricultura Tropical, Cali, Colombia. 667 pp. l5l Skerman, P.J., Cameron, D.G. & Riveros, F., 1988. Tropical forage legumes. Food and Agriculture Organization, Rome, Italy.

95

pp. 243-255. 161Teitzel, J.K. & Burt, R.L., 1976. Centrosema pubescens in Australia. Tropical Grasslands 10: 5-14. J.K. Teitzel &Chen Chin Peng

C h r o m o l a e n a o d o r a t a (L.) R.M. K i n g & H. R o b i n s o n Phytologia 20:204 (1970). COMPOSITAE

2« =40 Synonyms Eupatorium odoratum L. (1759), E. conyzoides Vahl (1794), Osmia odorata (L.) Schultz-Bip. (1866). Vernacular n a m e s Siam weed, Christmas bush, goat weed (En). Jack in the bush (Am). Herbe du Laos, fausse ramie, fleurit-Noël (Fr). Indonesia: ki rinyu (Sundanese). Malaysia: Siam weed, pokok kapal terbang. Philippines: devil weed, gonoi, (hulo)hagonoy. Burma (Myanmar) : bi-zat, tawbizat, curse of Caylan. Cambodia: tontrien khaèt. Laos: hnha:z fàlangx (general), hnha:z khi:lo:z (Paklay), nroj pawm tshis (hmong). Thailand: sapsua, ya-suamop. Vietnam: c[os] hoi, c[os] Lao, y[ee]n-bach. Origin and geographic distribution Siam weed originated in the humid tropics of the New World, where it occurs from southern Florida to northern Argentina. It has been introduced and is naturalized throughout humid, tropical Asia, from the Western Ghats in India throughout Indochina and Malesia to south-eastern Australia and the Mariana Islands in the east. It is found in the humid tropics of West and Central Africa and in south-eastern South Africa. Uses Although, under certain conditions, Siam weed is one of the most noxious weeds in agriculture and range management, it is also used as a green manure and mulch crop. In Cambodia it is used as a green manure in the production of lowland rice, cassava and black pepper. In Nigeria its use as mulch in yam, cassava and coffee is subject of research. It is recommended for the control of Imperata cylindrica (L.) Raeuschel. In Asia and Africa a natural fallow of Siam weed is becoming gradually more common in semi-permanent food crop production, and many small farmers in e.g. Indonesia and Laos consider it a most useful fallow crop. A protein extract from the leaves was in use as a poultry feed during the civil war in Nigeria. Siam weed is not palatable to cattle and large tracts of extensively managed pasture land have been

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abandoned because of uncontrollable Siam weed infestation. Leaves of Siam weed are reported to be useful in controlling the weevil Cylas formicarius and the butterfly Phtorimae operculella in sweet potato, the nematode Heterodera marioni in black pepper, as well as nematodes in sugar cane and tomato. Siam weed is used as a medicine for intestinal pains, colds and cough in the Caribbean region; in Ivory coast, for healing wounds, as a purgative, a remedy against cough, malaria, smallpox and yellow fever. In Thailand, C. odorata is traditionally used to stop bleeding. Properties At the end of the dry season a Siam weed fallow contains per 100 g dry matter: leaves: N 2.1-3.0 g, P 0.17-0.21 g, K 1.4-1.6 g, Ca 1.61.9 g, Mg 0.4-0.5 g; branches: N 0.2-0.4 g, P 0.02-0.03 g, K 0.6-0.8 g, Ca 0.3 g, Mg 0.2 g; litter: N 0.5-0.7 g, P 0.03-0.04 g, K 0.3-0.5 g, Ca 0.70.9g,Mg0.2 g. Leaves and petioles have glandular dots emitting a strong pungent smell when crushed. Phenols and alkaloids in the plant, in particular in the leaves, have an allelopathic effect, inhibiting the germination ofits own seeds and seedling development of other plants. Siam weed contains essential oils having an anti-bacterial activity on Staphylococcus aureus and Escherichia coli. Applied as a green manure in rice paddies, it may kill fish. It contains 4',5,6,7-tetramethoxyflavone, which enhances blood coagulation. The weight of 1000 fresh achenes is about 0.25 g. Description A spreading, much-branched, tangled, thicket-forming, perennial shrub, up to 3 m tall, scrambling up to 7 m. Root system rather superficial, upper part of the root growing horizontally and swollen, but taproot growing deep and massive. Stem profusely branched, herbaceous when young, tough and semi-woody when older, cylindrical, finely striate, yellowish, shortly hairy or nearly glabrous; branches slightly ridged longitudinally, pubescent. Leaves simple, opposite; petiole 1-3 cm long or more, glabrous or sparingly pubescent; blade ovate-triangular, conspicuously 3(-5)-veined, 5-14 cm x 2-8 cm, acuminate, margins toothed, dotted with glands, sparsely hispidhairy to glabrous, often purple when young. Inflorescence a homogamous, 10-35-flowered head, arranged in corymbose clusters arising from the axils of upper leaves; peduncle 1-2 cm long; involucre cylindrical, 8-10 mm x 3-4 mm, bracts in 5 or 6 rows, closely overlapping, oblong, increasing in size upwards, up to 10 mm x 3 mm, strawcoloured to greenish; corolla tubular, 5 mm long,

Chromolaena odorata (L.) R.M. King & H. Robinson - 1,flowering branch; 2, flower head; 3, flower; 4, achene with pappus; 5, achene without pappus. 5-lobed, pale mauve, pale blue or whitish, protruding from the involucre; stigma with a long, exserted arm. Fruit a narrow achene, linear, angular, 3-5 mm long, brown or black, with short, white, stiff hairs along the edges; pappus white, consisting ofrough bristles, 4-5 mm long. Seed minute. Growth and development Viability of fresh seed ranges from 33-66%. After 2 years up to 40% of the seed still germinates. A small proportion of the seed germinates when mature, but most remains dormant. Seeds are photoblastic, but they may emerge when buried up to 3 cm deep. Emergence takes 4-12 days. During the first 3 months the seedlings stay rather small and mainly form leaves. Later, the length and biomass of the stem increase rapidly. Before growing downwards, the primary root forms a small, horizontal part, from which many secondary roots develop. During further growth it swells progressively and serves as a storage organ from which new shoots may sprout. Plants start branching after reaching a height of about 120 cm. The shoots of Siam weed bend over

CHROMOLAENA

due to their increasing weight. Consequently, apical dominance is broken and new shoots develop. The bent shoots die and form a thick, sagging mat in the vegetation which absorbs the light of plants in the understorey and hinders their vertical development by mechanical pressure. Siam weed is a pioneer species, suppressing grasses in the succession from open space to forest, making it a noxious weed in rangelands. Its lifetime depends on the presence of woody species in the vegetation. In India and Ivory Coast Siam weed diminishes from the fifth year onwards, as tree species start shading it out. When shrubs and trees are absent the lifetime of Siam weed may exceed 15 years. Siam weed flowers annually from the first year. Time of flower initiation and inflorescence development may differ among plants and even among branches of one plant. The central cyme of the inflorescence flowers slightly earlier than the peripheral ones. Pollination is by insects. Apomictic fruit development also occurs. The period from flower initiation to fertilization is about 1.5 months, from fertilization to seed dispersal takes another month. Flower initiation is rather complex: shorter daylengths, diminishing rainfall and falling temperatures seem decisive factors. The number of seeds produced is often extremely high. Production of 100 000-180 000 seeds/m 2 has been recorded in natural stands of Siam weed. Seeds are dispersed mainly by wind, but dispersal by animals and humans are important as well. Vegetative growth stagnates during flowering and seed production. After flowering most leaves wither and fall. New leaves and shoots grow from the old leaf axils, while the dead terminal part of the stems with the old inflorescences drop off. Other botanical information C. odorata has been excluded from the genus Eupatorium L.; it can be distinguished by its rather consistent pattern of many rows of bracts, giving a cylindrical appearance to the head, by the 3 prominent veins ofthe leaves, and by the pungent smell of crushed leaves. In Hawaii, the name Eupatorium odoratum is often used for Ageratina adenophora (Spreng.) R.M. King & H. Robertson. The name Eupatorium conyzoides Miller is a synonym of Vernonia arborescens Swartz, but is sometimes used erroneously for C. odorata. Ecology The natural habitat of Siam weed includes forest clearings, river banks and borders between savanna and closed forest. It can be found from sea level up to 1000(-1500) m altitude. Minimum annual rainfall required is 1100 mm,

with a dry season of up to 5 months, although it can be found sporadically at 700 mm annual rainfall. It is not found in temperate regions and a mean daily temperature of 25-30°C is optimal. Siam weed is heliophile. It needs light to germinate and is suppressed when shaded by other plants. It grows on a wide range of soils, but not on inundated sites. Through symbiosis with vesicular-arbuscular mycorrhizae it can grow well on soils poor in P. Under a Siam weed fallow the soil structure improves and the pH and biological activity ofthe soil increase. It tolerates mechanical injuries caused by slashing and burning, as it is able to form new shoots on the swollen part of the root. However, frequent injuries deplete the plant's regenerative capacity. Propagation and planting To date Siam weed has not been planted as a crop. It normally grows from seed, but can be propagated vegetatively, as the nodes of branches readily root when in contact with moist soil. Husbandry Under humid tropical lowland conditions in Ivory Coast biomass production of a natural stand of Siam weed at the end of the dry season varied from 14.4 t/ha after 2 years to 21.7 t/ha after a 4 years fallow, supplying 70-140 kg N, 5-8 kg P, 109-125 kg K, 70-160 kg Ca and 30-50 kg Mg per ha. Regrowth of Siam weed after cropping is best when the impact of cultural practices during cropping is modest and the cropping period is limited to 1 or 2 seasons. Under humid tropical conditions a mulch of 8.5 t dry matter/ha, half of it composed of leaves and young shoots, will be decomposed in 38 days. In trials in Cambodia a mulch of 20 t/ha of Siam weed increased rice yields from 1.5 t/ha to 2.8 t/ha. This increase was similar to that resulting from an application per ha of 30 kg N, 30 kg P and 30 kg K applied as chemical fertilizer. The combination of green manure with chemical fertilizer increased rice yield to 4.3 t/ha. Ploughing in the green manure or leaving it as mulch on the soil surface were equally effective. The Siam weed green manure repelled crabs from the rice field, but also killed the fish in the paddies. Considerable increases in yield were also found in cassava. Mulching black pepper with Siam weed reduced the nematode infestation (Heterodera marioni) and secondary infection of Pythium spp. All the pepper vines in the untreated plots died within 3 years, but nearly all survived in the mulched plots. In low input agriculture slashing and burning the fallow crop before planting and an early weeding

97

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proved most appropriate to reduce the development of Chromolaena as a weed. In perennial cropping and forest plantations it can be controlled by repeated slashing and will eventually be shaded out when the canopy closes over. However, it hampers the establishment of a leguminous ground cover. In Malaysia it has been shown to depress the growth ofrubber trees. Siam weed is known to harbour parasites and pathogens injurious to crops, like grasshoppers (Zonocerus variegatus), weevils (Aphis spp.), nematodes (Scutellonema bradys) and microorganisms (Cercospora spp. causing leaf spot disease, Fusarium oxysporum and Pseudomonas solanacearum). Diseases and pests Although many pathogens and insects have been found on Siam weed, they rarely do serious harm. Only the arctiid moth Pareuchaetes pseudoinsulata and the seed-feeding weevil Apion brunneonigrum, both oligophage insects originating from tropical America, are known to cause considerable damage to Siam weed. They have been introduced into several African and Asian countries for the biological control of this weedy plant, with varying degrees of success. Prospects Due to its fast growth and nutrient accumulation and its copious litter production, Siam weed may play an important role as a fallow crop for restoration of soil fertility in cropping systems where shortening of the fallow period is inevitable. Used as a mulch it may contribute to the increase or maintenance of soil fertility and the improvement of the physical condition of the soil. Due to its rapid lateral spreading and superficial rooting, Siam weed also has good prospects for the control of soil erosion and Imperata cylindrica. However, more research is needed to incorporate Siam weed into semi-permanent cropping systems and to develop adequate measures to control its weediness in extensively managed crop production and rangeland systems. Literature 111 Audru, J., Berekoutou, M., Deat, M., de Wispelaere, G., Dufour, F., Kintz, D., le Masson, A. &Menozzi, Ph., 1988. L'herbe du Laos - Synthèse des connaissances actuelles sur la plante et sur les moyens de lutte [Siam weed survey of actual knowledge of the plant and of methods of its control]. Etudes et synthèses de 1'IEMVT No 28. Institut d'Elevage et de Médecine Vétérinaire des Pays Tropicaux, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Maisons-Alfort, France. 186 pp. 121 Dove, M.R., 1986. The practical

reason of weeds in Indonesia: peasant vs. state views of Imperata and Chromolaena. Human Ecology 14(2): 163-190. I3l Gautier, L., 1992. Contact forêt-savane en Côte d'Ivoire centrale: Rôle de Chromolaena odorata (L.) R. King & H. Robinson dans la dynamique de la végétation [Contact forest-savanna in central Ivory Coast: role of Chromolaena odorata (L.)R. King &H. Robinson in the dynamics of the vegetation]. Conservatoire et Jardins Botaniques de la ville de Genève, Genève, Switzerland. 258 pp. 141 Holm, L.G., Plucknett, D.L., Pancho, J.V. & Herberger, P.D., 1977. The world's worst weeds - distribution and biology. University Press of Hawaii, Honolulu, United States, pp. 212-216. I5l Litzenberger, S. &Lip, Ho Tong, 1961. Utilizing Eupatorium odoratum L. to improve crop yields in Cambodia. Agronomy Journal 53: 321-324. 161 Lucas, E.O., 1989. Siam weed (Chromolaena odorata) and crop production in Nigeria. Outlook on Agriculture 18(3): 133-138. I7l Muniappan, R. &Ferrar, P. (Editors), 1991.Ecology and management of Chromolaena odorata. BIOTROP Special Publication No 44. ORSTOM and SEAMEO BIOTROP, Bogor, Indonesia. 167 pp. 181 Muniappan, R. &Marutani, M., 1988. Ecology and distribution of Chromolaena odorata in Asia and Pacific. In: Muniappan, R. (Editor): Proceedings of the First International Workshop on biological control of Chromolaena odorata, Feb. 29-Mar. 4, 1988, Bangkok, Thailand. Agricultural Experiment Station, Mangilao, Guam, United States, pp. 21-24. I9l Roder, W., Phengchanh, S., Keoboualapha, B. & Maniphone, S., 1995. Chromolaena odorata in slash-and-burn rice systems of Northern Laos. Agroforestry Systems 31: 79-92. 1101Slaats, J.J.P., 1995. Chromolaena odorata fallow in food cropping systems. An agronomic assessment in South-West Ivory Coast. PhD thesis. Wageningen Agricultural University, Wageningen, the Netherlands. 177 pp. J.J.P. Slaats

Cordia alliodora (Ruiz & Pavon) Oken Allg. Naturgesch. 3(2): 1098 (1841). BORAGINACEAE

2« =C. 72 Synonyms Cerdana alliodora Ruiz & Pavon (1799), Cordia cerdana (Ruiz & Pavon) Roemer & Schultes (1819),Lithocardium alliodorum (Ruiz & Pavon) Kuntze (1891). Vernacular n a m e s Cordia (general and trade name in the Americas), salmwood (trade name in

CORDIA

the United Kingdom) (En). Spanish elm (Am). Bois soumis, chêne caparo, bois de rose (Fr). Laurel, cypre, capa prieto (Sp). Origin and geographic distribution C. alliodora is indigenous to dry and wet forest from Mexico and the Antilles to Brazil and Bolivia. It is now widely distributed in tropical America from northern Argentina to central Mexico and in the Caribbean islands. It has been introduced to Africa, Asia (Nepal, Sabah and Sri Lanka) and the Pacific region (Hawaii, Solomon Islands, Vanuatu). U s e s C. alliodora produces high quality timber widely used where it occurs naturally. Because of its tall, straight stem, self-pruning habit and compact crown, combined with the ease with which it regenerates naturally on cleared sites, it is commonly grown in association with many agricultural crops and in numerous agroforestry systems, e.g. as shade tree in coffee and cocoa plantations and in pastures, often in combination with Erythrina poeppigiana (Walpers) O.F. Cook. Its leaves and seeds have medicinal properties, the fruits are edible, if not very tasty, and its flowers are known to bee-keepers as a major source of nectar. The tree is planted as an ornamental because of its abundant, attractive, white, fragrant flowers. The wood is used in construction, e.g. for doors, window frames, panelling, flooring, and for furniture, cabinet work, turnery, carving, scientific instruments, boats (including bridge decking), oars, sleepers, veneer, fuelwood and charcoal. Properties Wood of C.alliodora is easy to season and work and produces an attractive finish (pale golden-brown to brown with darker streaks). It has dimensional stability when dry, satisfactory mechanical characteristics, and is moderately durable to fungus attack with good resistance to termites. Basic density of the wood shows wide variation, 380-520 kg/m 3 for natural forest samples from Central America. In Costa Rica, where it is found from tropical dry to tropical wet forest, basic density varies from 380-620 kg/m 3 in naturally regenerated trees. Trees grown under drier conditions have the highest values. The density of the wood of plantation-grown trees in Vanuatu ranges from 270-530 kg/m3. The weight of 1000 seeds is 15-50 g. Description A large tree, up to 25(-40) m tall, with or without buttresses. Bark of young trees smooth and greenish, becoming greenish-black and sometimes narrowly fissured with age. Twigs stellate-pubescent when young, ending in obovoid

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Cordia alliodora (Ruiz & Pavon) Oken - 1, flowering branch; 2, vertical section through flower; 3, fruit. ant domatia. Leaves alternate, simple, deciduous, stellate-pubescent; petiole 0.5-3.5 cm long; blade elliptical to slightly obovate, up to 20.5 cm x 8.5 cm, glabrous to densely stellate-pubescent. Inflorescence terminal, usually arising from an obovoid ant domatium, paniculate, up to 25(-30) cm broad, branches usually densely stellate-pubescent; pedicel up to 1.5 mm long; flowers many, about 1 cm long and wide, white; calyx tubular, 4-6 mm long, grey-green, 10(-12)-ribbed, (4-)5(-6)-toothed, densely stellate hairy; corolla tubular, (4-)5(-6)-lobed, up to 14 mm long, white, tube up to 8.5 mm long, lobes oblong and rounded, spreading, up to 8.5 mm long; stamens (4-)5(-6), erect, white, lower part connate with corolla; pistil with 2-forked style, each fork ending in 2, clavate stigma lobes. Fruit an ellipsoid nutlet, 4.5-8 mm x 1-2.5 mm, completely enveloped by the persistent corolla and calyx, the wall thin and fibrous. Seedling with epigeal germination. Growth and development Seedlings develop a strong taproot. Later, spreading roots also develop which may grow into buttresses. Flowering

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may start when the trees are only 2 years old, but more commonly between 5-10 years after planting. Time of flowering and maturation of the fruit varies with locality; in Panama, flowering starts at the onset of the dry season. Lepidoptera are generally responsible for pollination. The mature fruit is shed with the withered flower still attached, which acts as a parachute during fruit fall, possibly assisting wind dispersal. The bole is generally straight and cylindrical and often clear of branches 50-60% of the total tree height, even in open, uncrowded conditions. Other botanical information The species is often incorrectly referred to as Cordia alliodora (Ruiz & Pavon) Cham. The genus contains about 300, mostly neotropical species and includes many useful timbers and some ornamentals with vivid, orange-red flowers. The flowers of C. alliodora vary from short-styled to forms with the stigma and anthers borne at about the same height, but individual plants have a constant ratio of anther and stigma height. The extent to which ant domatia are formed varies throughout the natural range. Domatia are is most prominent in Central America and north-western South America and almost absent in the West Indies and southern South America. The crushed leaves and the inner bark have an odour ofgarlic ('alliodora'). Ecology C. alliodora is a pioneer plant, found in a wide range of habitats from sea level up to 1000(-2000) m. Optimal growth occurs where mean annual rainfall exceeds 2000 mm and the mean annual temperature is about 24°C. It is also common in drier areas with only 750 mm rainfall, but growth is slower and form of stem and crown poorer. It is a strong light-demander that readily colonizes exposed soils. Plantations ofC. alliodora exposed to hurricanes and cyclones have shown above-average resistance to stem break and wind throw. A range of soil types is tolerated. Fertile, freelydrained conditions are preferred. Growth on degraded soils and on sites with poor drainage is reduced. C. alliodora is particularly suitable for calcareous soils in the more humid tropics. Propagation and planting C. alliodora is readily propagated by seed or by stem cuttings. Timing of seed collection is important to ensure a high germination rate, generally up to 80%. Shaking of branches to allow mature seed with a high viability to drop is the best method. Viability of fresh seed decreases rapidly under natural conditions; dried to below 10% moisture it may be

stored at 2°C for up to 10 years. Seed germinates in 5-20 days. Vegetative propagation is possible. Stumps are the type of planting stock generally used due to the ease and cheapness of the technique and the robust planting material produced. Seedlings, however, are known to have a more rapid early growth and may be used in cases where rapid canopy closure is required. Direct sowing and Wildlings are sometimes used in plantation establishment, although more intense weed control is then generally necessary. Choice of provenance is important. In plantations a planting density of4-5 m x 4-5 m is recommended. If a narrower spacing is used, thinning after 3-4 years is needed. In agroforestry spacing is adjusted to the associated crops. In coffee plantations in Costa Rica the optimum density of C. alliodora appears to be 100 mature trees/ha. The number of trees counted in agroforestry plots in Costa Rica ranges from 70-290/ha. Diameter increment in these plots was related to the associated crops and increased in the order pasture, sugar cane, coffee and cocoa. Husbandry Regular weeding is crucial in the early stages of establishment. Organic matter accumulation in a cocoa plantation in Costa Rica with C. alliodora planted at 6 m x 6 m amounted to 87-110 t/ha in 10 years and the trees had a mean annual increment of 7.4 nrVha. C. alliodora reduces the yield of cocoa, but the income generated from the timber compensates for this yield reduction. Farmers in Central and South America rely mostly on natural regeneration of C. alliodora for shade trees, but increased use of herbicides may reduce the number ofregenerating trees. Young to middle-aged trees coppice readily and suckers are sometimes abundant. Diseases and pests The rust fungus Puccinia cordiae is economically damaging to C. alliodora in its natural range. Other diseases noted to cause damage are a root disease caused by Phellinus noxius and a stem canker caused by Corticium salmonicolor in Vanuatu. Yield On suitable sites, with good management, annual growth of2m in height and 2 cm in diameter may be obtained during the first 10 years. Dimensions of 30-40 m height and 40-55 cm diameter at breast height are predicted for rotations of 20-25 years. In a 34-year-old plantation the mean annual increment of the C. alliodora trees was 8.8-20.3 nrVha; however, up to 36% ofthis volume was lost due to buttresses, stem irregularities,

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heart rot, forking, and inefficient wood extraction. Genetic resources Wide variation in morphology and performance is observed in the natural populations of C. alliodora. Provenance trials in Central America revealed that germination is more rapid and seedling growth faster for provenances from the Pacific watershed which experience a more pronounced dry season. However, growth rates of Atlantic provenances are superior within two years after planting, after initial slow development. Breeding The results of provenance trials are stimulating increased activities in the field of selection and breeding, e.g. in Vanuatu. C. alliodora is known to have a high degree of self-incompatibility. Other Cordia species are known to be either dioecious or heterostylous with associated self-incompatibility. Prospects The use of C. alliodora in exotic plantings and agroforestry shows promise due to its rapid growth, good stem form and fine wood. Its success in Central America bodes for good in South-East Asia. Further research on its use in silvopastoral systems is needed, especially with regard to resistance to trampling. The relation between wood quality, growth and provenance also needs to be evaluated further. Literature 111 Fassbender, H.W., Beer, J., Heuveldop, J., Imbach, A., Enrfquez, G. & Bonnemann, A., 1991.Ten year balances of organic matter and nutrients in agroforestry systems at CATIE, Costa Rica. In: Jarvis, P.G. (Editor): Agroforestry: principles and practice. Proceedings of an international conference, held at the University of Edinburgh, United Kingdom, 23-28 July 1989. Forest Ecology and Management 45(1-4): 173183. 121Greaves, A. & McCarter, P.S., 1990. Cordia alliodora. A promising tree for tropical agroforestry. Tropical Forestry Papers 22, Oxford Forestry Institute, Department of Plant Science, University of Oxford, United Kingdom. 37 pp. 131 Johnson, P. & Morales, R., 1972. A review of Cordia alliodora (Ruiz & Pav.) Oken. Turrialba 22(2): 210-220. 141 Miller, J.S., 1988. A revised treatment of Boraginaceae for Panama. Annals of the Missouri Botanical Garden 75: 456-521. 151Neil, P.E., 1988. Root disease (Phellinus noxius (Corner) G.H. Cunn.) of Cordia alliodora in Vanuatu. Commonwealth Forestry Review 67(4): 361-372. 161 Sommariba, E.J. & Beer, J.W., 1987. Dimensions, volumes and growth of Cordia alliodora in agroforestry systems. Forest Ecology and Management 18(2): 113-126. P.E. Neil &A.C.J, van Leeuwen

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Crotalaria micans Link Enum. pi. hort. berol. 2:228 (1822). LEGUMINOSAE - PAPILIONOIDEAE

2« = 16 Synonyms Crotalaria anagyroides Kunth (1824). Vernacular n a m e s Caracas rattlebox (Am). Thailand: hinghai. Vietnam: s[uj]c s[aj]c cao, s[uj]c s[aj]c soc. Origin and geographic distribution C. micans originated from Central and South America. It has been introduced into many tropical and subtropical countries, including those in Malesia, where it also naturalized locally. Uses In Central and South America, Indo-China, Indonesia, Malaysia, and Sri Lanka, C. micans is grown as a green manure and cover crop, for instance in plantations of coffee, tea, tobacco and rice. Young shoots and leaves are used as fodder for cattle. It is widely grown as an ornamental. Properties Unlike many other Crotalaria spp., C. micans is reported to be highly palatable and non-toxic to cattle. Young vegetative material contains per 100 g dry matter: crude protein 23 g, crude fibre 28 g, ash 7.2 g, ether extract 2.2 g, nonfibre extract 39.6 g, Ca 0.57 g, P 0.28 g. Tests in Colombia indicated per 100 g dry matter: N 3.6 g, K2.0g, Ca2.1g,Mg0.3g. The weight of 1000 seeds is 18 g. Botany Shrub up to 4 m tall; young branches angular, appressed pubescent. Leaves trifoliolate; petiole 3-5 cm long, longitudinally grooved above; stipules linear, 0.5-7 mm long, caducous; leaflets oblong-lanceolate to narrowly elliptic, 4-10 cm x 1-4.5 cm, apex acute to acuminate or obtuse, base cuneate, lower surface and midrib above puberulous, upper surface glabrous, lateral leaflets slightly smaller than the terminal one. Inflorescence a rather dense, 15-30-flowered raceme, 15-30 cm long, terminal, often leaf opposed; bracts linear, about 1 cm long, very early caducous; pedicel 5-9 mm long; bracteoles similar to bracts but smaller, very early caducous, inserted just above the middle part of the pedicel; flowers bisexual, 5-merous; calyx 8-13 mm long, appressed puberulous, tube campanulate, 5-6 mm long, bilabiate and 5-lobed, lobes longer than the tube, upper lobes triangular-acuminate, often coherent at the tips with the lateral lobes and woolly on the inside of the margins; corolla 14-18 mm long, yellow, purplish-veined; standard ovate-circular to slightly reniform, 13-14 mm x 18-21 mm,

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Crotalaria micans Link - 1, flowering branch; 2, flower; 3,fruiting branch; 4, seeds.

Ecology C. micans is tolerant of a wide range of climatic and soil conditions. It grows best in lowland areas, but is generally grown up to 1600 m altitude. In Java, it is found up to 1800 m altitude, and in Colombia even as high as 2600 m. Full sunlight is required for good seed production. Seed production is poor at high elevations. Agronomy C. micans is propagated by seed. When broadcast, a seed rate of 20-35 kg/ha is used; 6-12 kg/ha is adequate for sowing rows 0.9-1.5 m apart. In Java it is sown at the onset of the drier season in May-June. In established tea plantations it is sown immediately after pruning. Once established it will reseed itself. In Java fungal diseases are reported caused by the fungi Corticium salmonicolor and Sclerotium rolfsii. The dadap fungus (Septobasidium bogoriense), which also affects Erythrina spp. grown as shade trees, grows on the base of the stem, making it susceptible to other diseases. C. micans is a host of Lasiodiplodia theobromae affecting both cocoa and tea. The crotalaria bug (Ragmus importunatas) living on the underside ofleaves and on the tips of branches causes leaves to turn yellow. The damage can be so serious t h a t the cover crop has to be removed. It also attacks several Asian Crotalaria spp., but not C. pallida Aiton or C. trichotoma Bojer.

glabrous; wings oblong, 12-15 mm long, claws 3-4 mm long; keel 13-15 mm long, abruptly rounded a little below the middle, with a slightly incurved, untwisted beak; stamens 10, monadelphous, anthers dimorphic, 5 anthers basifixed, with filaments 3-6.5 mm long, 5 anthers dorsifixed, with filaments 4-9.5 mm long; style 8-11 mm long, curved, persistent, pubescent. Fruit an inflated, short-stipitate pod, subcylindrical, 3-4 cm x 1 cm, appressed puberulous, brown, dehiscent, with 16-20 seeds. Seed unequal-sided heart-shaped, about 4.5 mm x 3.5 mm, fine papillate, yellowishbrown. Early growth ofC.micans is fast, giving it a competitive advantage over most weeds. It can cover the soil in 3 weeks after germination and may reach 2.5 m after 3 months and 3.5 m after 6 months. In Bogor, Indonesia, the first seeds mature 7 months after sowing. C. micans forms root nodules with Bradyrhizobium spp. and fixes nitrogen. C. micans is characterized by terminal inflorescences on which the large flowers are grouped tightly with prominent, long curled bracts and bracteoles.

C. micans can be cut repeatedly, provided it is not cut too low and a few leaves per stem are left. It is easily incorporated into the soil as the lower stem does not start to lignify until 4 months after planting. Decomposition is rapid: in tests in Colombia, 40% of a crop was decomposed after 1 month and 60% after 2 months. However, in tea plantations in Java it is recommended to incorporate it into the soil 6 weeks before tea is planted. From Java, yields of 40 t/ha fresh material 4 months after planting are reported, containing about 150 kg nitrogen, while in the southern United States, 6 months after planting 4.5 t/ha dry matter containing 100 kg nitrogen has been reached. Genetic resources and breeding A germplasm collection of Crotalaria L. is being maintained by the United States Department of Agriculture, including material of C. micans. It is unlikely that any substantial breeding programme exists. Prospects C. micans is a useful multipurpose crop that can be grown for erosion control and for either green manure or fodder. Literature 111 Backer, C.A. &van Slooten, D.F., 1924. Geïllustreerd handboek der Javaansche

CROTALARIA

theeonkruiden en hunne beteekenis voor de cultuur [Illustrated handbook of weeds of Javanese tea plantations and their significance for teagrowingl. Ruygrok, Batavia, Dutch East Indies. 128, 128a. 121Godefroy, J., 1988. Observations de l'enracinement du stylosanthes, de la crotalaire et de flemingia dans un sol volcanique du Cameroun [Observations on the rooting of Stylosanthes, Crotalaria and Flemingia in a volcanic soil in Cameroon]. Fruits 43: 79-86. I3l Niyomdham, C , 1978. Arevision ofthe genus Crotalaria Linn. (Papilionaceae) in Thailand. Thai Forest Bulletin (Botany) 11: 105-181. 141 Polhill, R.M., 1982. Crotalaria in Africa and Madagascar. Balkema, Rotterdam, the Netherlands, p. 371. 15! SuarezVasquez, S. & Carillo-Pachon, I.F., 1976. Descomposición biológica de leguminosas y otros materiales de la zona cafetera Colombiano [Biological decomposition of legumes and other plant materials from the Colombian coffee area]. Cenicafé 27: 67-77. 161Windler, D.R. & McLaughlin, L., 1980. Crotalaria. In: Dwyer, J.D. et al. (Editors): Flora of Panama, Part 5, fasc. 5.2, Family 83: Leguminosae. Annals of the Missouri Botanical Garden 67: 606-607. C. Niyomdham

Crotalaria pallida Aiton Hort. kew. 3:20(1789). LEGUMINOSAE - PAPILIONOIDEAE

2n = 16 Synonyms Crotalaria mucronata Desv. (1814), C. striata DC. (1825), C.siamica Williams (1905). Vernacular names Smooth rattlebox, salts rattlebox (Am). Indonesia: kekecrekan (Sundanese), orok-orok (Javanese), telpok (Madurese). Malaysia: giring-giring, rang-rang. Philippines: gorunggorung, kolong-kolong, tambarisa. Cambodia: chângrô:ng sva:, dâng hot khmaôch, sandaèk ku:öy. Laos: hingx ha:y. Thailand: hinghai, honghai. Vietnam: l[uj]c l[aj]c ba l[as] tr[of]n, c[aa]y mu[oox]ng tr[af], c[af] ph[ee] r[uw]ng. Origin and geographic distribution C. pallida is probably a native of tropical Africa, but its natural distribution is obscured by widespread cultivation and subsequent pantropical naturalization. In Asia it is common in India and Sri Lanka and throughout South-East Asia. Uses C.pallida is used as a ground cover and a green manure crop throughout the humid tropics, though on a limited scale. In tea, rubber and coconut plantations in Sri Lanka and South-East

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Asia, and in cocoa plantations in West Africa, it is used as a green manure and planted in the interrows to reduce erosion. It is one ofthe oldest green manure crops in Indonesia, but lost popularity because of its susceptibility to diseases and pests. C. pallida replaced the more toxic Crotalaria spectabilis Roth in the south-eastern United States and was grown extensively for soil sanitation and as a green manure crop until the 1960s. It also has some value as a forage crop. However, its use is no longer recommended as the seed occasionally gets mixed into fodder grains, causing poisoning. In West Java, a fermented product ('dage'), was formerly made from the seeds. Seeds were boiled for two hours, wrapped in banana leaves and left to ferment for several days to remove poisonous components. In Cambodia the flowers are used as a vegetable. In Indo-China a kind of coffee is prepared from roasted seed. In Vietnam, the roots are sometimes chewed with betel-nut. In traditional medicine, C.pallida is used to treat urinary problems. A poultice made of the roots is applied to painful swelling of joints, and an extract ofthe leaves is taken as a vermifuge. In Laos the plant is used to reduce fever. Properties Tests in Java and Sri Lanka indicated 4.2 g N in above-ground parts per 100 g dry matter; in Florida 2.8 gN was found. Seeds of many Crotalaria spp., including C. pallida, contain a number of pyrrolizidine alkaloids, such as mucronatine and monocrotaline which affect the liver and may kill birds and mammals. They are particularly insidious toxins, as their effects may only become apparent weeks or months after the animal has stopped eating the seeds. In C.pallida the concentrations are low and toxic effects have only been observed when chicks were fed the seeds for several weeks. Leaves contain an alkaloid poisonous to goats; dried leaves are not toxic. A lectin from C. pallida, which specifically agglutinates type A erythrocytes, is used in cytochemical research. The flavonoids apigenin and vitexin have been isolated from the bark and the leaves. The weight of 1000 seeds is about 5 g. Botany An erect, well-branched annual or short-lived perennial herb, up to 1.5(-3) m tall. Stem stout, puberulent, with slender longitudinal grooves; branches densely appressed hairy. Leaves trifoliolate; stipules filiform, up to 3 mm long, caducous or absent; petiole 2-8.5 cm long; leaflets variable, elliptical to obovate, 3-13 cm x 2-5(-7) cm, obtuse, often emarginate, sometimes apiculate, glabrous above, thinly appressed puberulous beneath. Inflorescence a terminal, short-

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Crotalaria pallida Alton - 1, flowering branch; 2, flower; 3, calyx; 4,fruiting branch; 5, seeds.

ly pedunculate raceme, 15-40 cm long, 20-30-flowered; bracts linear, up to 5 mm long, caducous; bracteoles inserted at the base of the calyx, filiform, 1-3 mm long; pedicel 4 mm long; calyx deflexed, tubular, 6-8 mm long, appressed puberulous, with 5 unequal lobes; corolla about 1.5 cm long, yellow, often reddish-brown veined; standard elliptical, 11mm x 8 mm; wings oblong-lanceolate, 8 mm x 3 mm; keel shallowly rounded, 11mm x 4 mm, with narrow, slightly projecting beak. Pod shortly stipitate, subcylindrical, 3-5 cm x 6-8 mm, 30-40-seeded, glabrescent, yellowish when mature. Seed heart-shaped, 3 mm x 2 mm, shiny, mottled ochre and dark grey-green or brown. C. pallida is cleistogamous and the percentage of outcrossing is usually small. Germination is quick, but initial growth is slow. After one month, 3 leaves and a well branched and nodulated root system have developed. In subtropical southern Brazil flowering starts about 160 days after sowing and the first mature seeds are released from the pods two months later. Two varieties of C. pallida are sometimes recognized: var. pallida with elliptical leaflets, widest in the middle, about 6-13 cm long, acute or round-

ed at the apex, and var. obovata (G. Don) Polhill with elliptical-obovate to obovate leaflets, widest at a point 0.6-0.8 of the length from the base to the apex, about 3-7 cm long, rounded or refuse at the apex. Var. obovata tends to occur in wetter locations. Intermediate forms are reported from Thailand. Ecology C. pallida occurs naturally on river banks, edges of lakes, extending into woodland, grassland and waste places from 0-1000 m altitude and may be planted to 1800 m. It is light-demanding and shade strongly retards development. It grows in a wide range of annual rainfall conditions, from 850 mm to over 3000 mm and occurs occasionally in rather dry locations. The average annual temperature varies from 16-26°C. Tests in Florida showed satisfactory growth on a wide range of soils, except on peat soils that developed under coarse grass. In West Africa it is considered well suited to sandy soils. In Thailand it is found in the tidal zone, growing in association with Avicennia sphaerocarpa Stapf ex Ridley and Ipomoea pes-caprae (L.) R. Br. It also occurs in open, secondary thickets with Bambusa bambos (L.) Voss, Chromolaena odorata (L.) R.M. King & Robinson and Lantana camara L. Agronomy Fresh seed ofC. pallida has a higher germination rate than stored seed. In India germination was found to be improved by treatment with hot water. However, other reports indicate less favourable results and even damage of seed. A seed rate of 10-20(-30) kg/ha is required. In Bogor, Indonesia, C. pallida sown in rows 50 cm apart covered the soil after three months. A few weedings were required. Plants have to be topped when about 30 cm tall to promote branching. C. pallida should be cut at least 20-25 cm above the ground to ensure good regrowth. It can be cut 3-4 times before it dies out, generally after 1.5-2 years. In Sri Lanka yields of 13.5 t/ha of above-ground green material have been obtained in 6 months, and 23 t/ha in 4 cuts in a little over a year, while annual yields ofup to 5.2 t/ha and 10.2 t/ha aboveground air-dry matter are reported from Florida and southern Brazil respectively. C. pallida is susceptible to the root-knot nematodes Meloidogyne incognita and M.javanica. It is one of the alternative hosts of Maruca testulalis, which is a pest in cowpea (Vigna unguiculata (L.) Walp.). It also acts as a vector for the 'kette' virus affecting cardamom (Elettaria cardamomum (L.) Maton). During dry periods, flea-beetles may cause severe defoliation. The bug Ragmus importunatas causes leaf fall at the beginning of the

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rainy season in Java. Other insects causing damage are the beetle Longitarsus sp. and the caterpillar Utetheisa lotrix. Genetic resources and breeding The Southern Regional Plant Introduction Station of the United States Department of Agriculture, Griffin, Georgia holds 26 accessions of C.pallida from 19 countries. Around 1960 cv. Giant Striata was the most popular cultivar in the south-eastern United States. About 90% of the seed sold in North Carolina was ofthis cultivar. Prospects C. pallida retains some importance as a cover, green manure and fodder crop in the south-eastern United States. In South-East Asia it will probably remain of minor importance only, as species more resistant to diseases and pests are available. Literature 111 Dagar, J.C., Jeyamurthy, A. & Sharma, A.K., 1988. An endeavour towards the utility of a common wasteland weed Crotalaria mucronata Desv. from Andaman (India). Journal of Economic and Taxonomie Botany 12(2): 489490. 121 Duke, J.A., 1981.Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 67-68. I3l Jackai, L.E.N. & Singh, S.R., 1981. Studies on some behavioral aspects of Maruca testulalis on selected species of Crotalaria and Vigna unguiculata. Tropical Grain Legume Bulletin 22: 3-6. I4l Polhill, R.M., 1982. Crotalaria in Africa and Madagascar. Balkema, Rotterdam, the Netherlands, pp. 184-186. I5l Rao, D.G. & Naidin, R., 1973. Studies on 'kette' or mosaic disease of small cardamom. Journal of Plantation Crops 6 (Suppl.): 129-136. 161 Sandanan, S. & Rajasinghham, C.C., 1982. Effect of mulching and cover crops on soil erosion and yield of young tea. Tea Quarterly 51(1): 21-26. 171 Sikdar, S., Ahmed, H. & Chatterjee, B.P., 1990. A pH dependent, low molecular weight, blood group-A-specific lectin from Crotalaria striata seeds: purification and carbohydrate specificity. Biochemical Archives 6(2):207-216. 181 Stokes, W.E., 1927. Crotalaria as a soil building crop. Journal ofthe American Society ofAgronomy 19:944-948. N.O. Aguilar

Crotalaria spectabilis Roth Nov. pi. sp.:341 (1821). LEGUMINOSAE - PAPILIONOIDEAE

2/1 = 16 Synonyms Crotalaria sericea Retzius (1788), non Burm.f. (1768).

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Vernacular n a m e s Showy rattlebox, showy crotalaria (En). Thailand: mahing men (northern). Origin and geographic distribution C. spectabilis probably originated in tropical Asia, but is now distributed pantropically. It is also cultivated throughout the tropics, including South-East Asia and in the south-eastern United States. Uses C. spectabilis is used as a green manure and for erosion control in the tropics and in the United States. Its use as fodder has ceased because of its toxicity. It is a spectacular ornamental, which flowers for long periods. A fairly strong fibre is extracted from the stem. In India, plants are used in the treatment of scabies and impetigoProperties The seed and other above-ground parts contain the pyrrolizidine alkaloid monocrotaline, which lowers blood pressure and is toxic to farm animals and probably also to root-knot nematodes (Meloidogyne spp.). Because of its bitterness the green material is avoided by farm animals. In Brazil, leaves contained per 100 g dry matter: N 4.0 g, K 1.2 g, Ca 1.1 g, Mg 0.4 g. The weight of 1000 seeds is 15 g. Botany Erect, much-branched annual herb, up to 2 m tall. Stem and branches angular, grooved, subglabrous. Leaves simple; stipules persistent, obliquely oblong-ovate, acuminate, 3-10 mm x 2-8 mm; petiole 2-8 mm long; blade oblanceolate to obovate, (5-)8-14 cm x 3-8 cm, upper surface glabrous, lower surface appressed pubescent. Inflorescence a rather lax, many-flowered raceme, 15-50 cm long; bracts persistent, cordate, 10-20 mm x 5-10 mm, acute or acuminate; pedicel 8-13 mm long; bracteoles lanceolate, 1-2 mm long; calyx campanulate, 11-14 mm long, with 5 unequal lobes which are longer than the tube, glabrous; corolla yellow; standard orbicular, about 20 mm in diameter; wings obovate-oblong, 9-18 mm x 5-9 mm; keel 10-14 mm x 4-9 mm, rounded about the middle, with a short, incurved, twisted beak; stamens 10, monadelphous; anthers dimorphic, with 5 long, basifixed anthers on a short filament alternating with 5 rounded, dorsifixed anthers on a long filament; ovary narrowly oblong, glabrous. Fruit a broadly clavate-oblong pod, 4-5 cm x 1.5-2.5 cm, glabrous, brown to dark brown when mature, 20-24-seeded. Seed unequal-sided heartshaped, about 3.5 mm x 4 mm, with the radicular side strongly incurved, brown. C. spectabilis is grown as an annual with a life cycle of 4-6 months. It develops an extensive root system that may reach to a depth of 120 cm. It nodulates with slow-growing Bradyrhizobium

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spectabilis had a dry matter production of 10-11 t/ha in 5 months, containing 170 kg nitrogen, slightly lower than Cajanus cajan (L.) Millsp. cv. Norman and Indigofera hirsuta L. The beneficial effect of C. spectabilis on the succeeding crop results not only from the increased nitrogen content of the soil but also from its effect on nematodes. The numbers of root-knot nematodes (Meloidogyne incognita and M. javanica) and of the sting nematode {Belonolaimus longicaudatus) in the soil are greatly reduced by a crop ofC. spectabilis. The reduction in root-knot nematodes has been shown to last until the harvest of a subsequent highly susceptible crop of cowpea (Vigna unguiculata (L.) Walp.). Reports on the effect on the lesion nematode (Pratylenchus brachyurus) are contradictory; its numbers increased slightly in Florida, but were reduced in experiments in Nigeria. When grown for seed, several caterpillars may attack the young pods. They may be very destructive, causing complete failure of the seed crop. Preventive use of insecticides is recommended. The fungus Alternaria cassiae has been tested as control agent for C. spectabilis where it has become weedy. Effective control in the field was achieved by spraying twice with a solution containing spores ofthe fungus. Crotalaria spectabilis Roth - 1, flowering branch; 2, flower; 3,fruiting branch; 4, seeds. spp. Flowering starts about 2 months after germination. Ecology C. spectabilis is a plant of the tropics and subtropics, requiring an annual rainfall of 900-2800 mm and a mean annual temperature of 12-28°C. It is drought-tolerant. It occurs in open locations along forest margins and as a weed in cultivated fields, from sea level up to 1500 m altitude, on a wide range of soils, including heavy soils, with a pH range of 4.8-8.0. Agronomy C. spectabilis is propagated by seed. A seed rate of 15-20 kg/ha is recommended in the United States, and of 90 kg/ha for broadcasting in Brazil. Seed should not be sown deeper than 5 cm. Germination is rapid and can be complete 5-6 days after sowing. A crop of C. spectabilis is easy to incorporate into the soil, as the lower part of the stem hardly lignifies. It should be ploughed in about 2 months before the following crop is sown or planted. This allows about 70% of the organic matter to decompose and release its nutrients. Tests on poor sandy soils in Florida found that C.

Genetic resources a n d b r e e d i n g Germplasm collections of Crotalaria spp. are maintained by the United States Department of Agriculture, including material of C. spectabilis. It is unlikely that any substantial breeding programmes exist. Prospects Its high growth rate and effective control of root-knot and sting nematodes make C. spectabilis a very useful green manure crop, deserving more attention in South-East Asia. Its effect on nematodes and potential as a trap crop for root-knot nematodes should be studied further. Literature 111 Everist, S.L., 1974. Poisonous plants of Australia. Angus & Robertson, Sydney, Australia, pp. 415-417. 121McSorley, R., Dickson, D.W., De Brito, J.A., Hewlett, T.E. & Frederick, J.J., 1994. Effects of tropical rotation crops on Meloidogyne arenaria population densities and vegetable yields in microplots. Journal of Nematology 26: 175-181. 131 Niyomdham, C , 1978.A revision of the genus Crotalaria Linn. (Papilionaceae) in Thailand. Thai Forest Bulletin (Botany) 11: 105-181. 141Polhill, R.M., 1982. Crotalaria in Africa and Madagascar. Balkema, Rotterdam, the Netherlands, p. 373. I5l Reddy, K.C., Soffes, A.R. & Prine, G.M., 1986. Tropical legumes for green manure. 1. Nitrogen production and the effects on

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succeeding crop yields. 2. Nematode populations and their effects on succeeding crop yields. Agronomy Journal 78: 1-4, 5-10. I6l Sabadin, H.C., 1984. Adubacäo verde [Green manure]. Lavoura arrozeira 37(354): 19, 22-26. I7l Suarez-Vasquez, S. & Carillo-Pachon, I.F., 1976. Descomposición biológica de leguminosas y otros materiales de la zona cafetera Colombiano [Biological decomposition oflegumes and other plant materials from the Colombian coffee area]. Cenicafé 27: 67-77. C. Niyomdham

Crotalaria trichotoma Bojer Ann. se. nat. Series 2.Vol. 4:265 (1835). LEGUMINOSAE - PAPILIONOIDEAE

2n = 16 Synonyms Crotalaria zanzibarica Benth. (1843), C. usaramoensis Baker f. (1914). Vernacular names Curare pea (En). West Indian rattlebox (Am). Indonesia: geger sore (Sundanese). Origin and geographic distribution C. trichotoma originates from the coastal regions of Tanzania and northern Mozambique. It was introduced into Java in 1916 by the Botanic Garden in Bogor. It was soon taken into cultivation and spread through Java and Sumatra, where it occasionally escapes from cultivation, but does not seem to naturalize. It is now distributed throughout the humid tropics and sometimes naturalizes (e.g. in Taiwan and Vietnam). Uses Because of its quick growth and good production of green matter C. trichotoma is grown as a green manure and cover crop in tea, coffee, rubber and citrus plantations. It is especially grown in locations where C. micans Link is severely attacked by Ragmus bugs or where a lower-growing cover is preferred. In Indonesia it has been tested as an intercrop in maize and as a green manure crop in vegetables. In Argentina, Central America and Angola it is grown for fodder, often in mixed swards with grasses. Properties The leaves and stems are very nutritious and are readily eaten by cattle and horses. Although poisonous alkaloids have been found in many other Crotalaria spp., C. trichotoma appears to be free of them. Its bark contains fibre, but this is of poor quality, unsuitable for making bags, possibly adequate for cordage. Botany Erect annual or short-lived perennial herb, up to 2.7 m tall, deep rooted, base often woody, upper part of stem well branched. Stem

Crotalaria trichotoma Bojer - 1, flowering branch; 2, flower; 3,fruiting branch; 4, seeds. ribbed, appressed puberulous. Leaves trifoliolate, without stipules; petiole 2-5 cm long; leaflets lanceolate to elliptical-oblong, 4-14 cm x 1-4 cm, base acuminate, apex acute or rounded, glabrous or rarely puberulous above, appressed puberulous below. Inflorescence a terminal raceme, 30-40 (-90) cm long; flowers many, closely arranged; pedicel 4-8 mm long; bracts linear-caudate, 2-4 mm long; bracteoles inserted at the base of the calyx or rarely on upper part of pedicel, linear, l-1.5(-2.5) mm long; calyx becoming truncate at base and deflexed against the pedicel, 4-6 mm long, glabrous or thinly appressed puberulous, the 5 lobes reduced to small, widely spaced teeth; standard obovate-elliptical or suborbicular, 10-13 mm wide, yellow, reddish-purple veined, glabrous outside; wings and keel about equal in size, wings with a dark mask at the base, keel 12-13 mm long, rounded about the middle, with a slightly incurved, sharp, untwisted beak; stamens 10, all joined, sheath open at least at the base, anthers dimorphic, 5 large ones alternating with 5 short ones; ovary stipitate. Pod shortly stipitate, subcylindrical, inflated, (30-)35-45 mm x 7-11 mm,

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black when ripe, appressed puberulous, 50-70seeded. Seed obliquely heart-shaped, 2-3 mm long, smooth, orange-buff or terracotta. C. trichotoma is self-incompatible and tests indicate that its flowers are pollinated by insects before they open, suggesting that it is cleistogamous and self-compatible. In the literature C. trichotoma is better known by its synonymous names. It resembles C.pallida Alton, in which the wings are shorter than the keel and lack the basal dark colouration. Ecology The natural habitat ofC.trichotoma is grassy sites in coastal forest clearings, bushland, Brachystegia woodland, grasslands, roadsides and cultivated fields, up to an altitude of 1800 m. In Java and Sri Lanka it is cultivated up to 1500 m altitude. On degraded and compacted soils it performs better than most other green manure crops. It is fairly tolerant of drought. Agronomy C. trichotoma is propagated by seed. Direct sowing at a rate of 2.5-3.5 kg/ha in strips about 0.3-1 m apart is most common. Sowing should not be done under very wet conditions. Two weedings are generally required before it covers the ground, which occurs after 3-4 months. Once established, C. trichotoma propagates abundantly by self-seeding. It produces a large amount of green matter but is rather short-lived and does not tolerate frequent heavy lopping. Cutting should be done at a height of 45-60 cm above the ground, always leaving a few leaves. Cutting at lower levels results in very poor regrowth. Green manure yields are generally slightly lower than from C. micans; a yield of 5t/ha, obtained 5 weeks after a previous harvest is reported from Bogor. A soil cover may contain about 25 t/ha fresh organic matter 6 months after planting. Little organic matter accumulation takes place thereafter, unless the plants are cut. C. trichotoma is sometimes severely attacked by the fungus Parodieila spegazzinii, which covers the upper surface of the leaves with a black sootlike layer. The affected leaves curl upwards and whole plantations can be destroyed. C. trichotoma is occasionally ravaged byHelopeltis antonii and less severely - by Deiopeia pulchella. It is resistant to Ragmus importunatas bugs, but may act as a host plant for the legume pod borer (Maruca testulalis) and the lima bean pod borer (Etiella zinckenella). Genetic resources and breeding Germplasmcollections of Crotalaria spp. are maintained by the United States Department of Agriculture, including material of C. trichotoma. It is unlikely

that any substantial breeding programmes exist. Prospects C. trichotoma is a very suitable green manure crop in plantation crops on poor, compacted soils and where other, more productive crops cannot be grown because of disease and pest problems. More research is urgently needed, especially on its economics and its incorporation in cropping systems with annual crops. Literature 111 Gillett, J.B., Polhill, R.M. & Verdcourt, B., 1971. Leguminosae (Part 4), Subfamily Papilionoideae (Part 2). In: Milne-Redhead, E. & Polhill, R.M. (Editors): Flora of tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom, pp. 911-913. 121 Backer, C.A. & van Slooten, D.F., 1924. Geïllustreerd handboek der Javaanse theeonkruiden en hunne beteekenis voor de cultuur [Illustrated handbook of weeds of Javanese tea plantations and their significance for tea-growing]. Ruygrok, Batavia, Dutch East Indies, p. 132, 132a. 131 Listeria, M.S., 1976. Pengaruh tumpang sari Crotalaria usaramoensis denganjagung sebagai bahan pupuk organik pada tanaman kentang dan pengaruhnya terhadap produksi jagung berikutnya [Evaluation of intercropping of C. usaramoensis and maize as a source of green manure for subsequent crops of potato and maize]. Bulletin Penelitian Hortikultura 4: 47-52. I4l Listeria, M.S. & Hekstra, A., 1976. Pengaruh kapur, pupuk NPK dan beberapa jenis pupuk organik pada tanaman-tanaman kentang, kacang jogo dan kubis [The effects of liming, NPK fertilizing and some other organic matter on potato, bean and cabbage]. Bulletin Penelitian Hortikultura 4: 3-13. 151 Polhill, R.M., 1990. Légumineuses [Leguminosae]. In: Bosser, J., Cadet, T., Guého, J. & Marais, W. (Editors): Flore des Mascareignes. Vol. 80. The Sugar Industry Research Institute, Mauritius, L'Institut Français de Recherche Scientifique pour le Développement en Coopération (ORSTOM), Paris, France & The Royal Botanic Gardens, Kew, United Kingdom, pp. 200-202. I6l Vidal, M.R.R., Vidal, W.N. & Mussury, R.M.A., 1990. Germinaçâo e desenvolvimento da plântula de Crotalaria zanzibarica Benth. [Germination and development of plantlets of C. zanzibarica]. Revista Ceres 37 (211): 185-198. L.P.A. Oyen

CYAMOPSIS

C y a m o p s i s t e t r a g o n o l o b a (L.) T a u b e r t Engler & Prantl, Natürl. Pflanzenfam. 3(3): 259 (1894). LEGUMINOSAE - PAPILIONOIDEAE

2« = 14 Synonyms Cyamopsis psoraloides (Lamk) DC. (1825). Vernacular n a m e s Guar, cluster bean, Siam bean (En). Cyamopse à quatre ailes (Fr). Malaysia: kottavarai (Malayalam, Tamil). Burma (Myanmar): pè-walee, walee-pè. Thailand: thuakua (central). Origin and geographic distribution Guar is a cultigen of uncertain origin. It has been speculated that guar originated in north-western India and Pakistan from Cyamopsis senegalensis Guill. & Perr. The latter species, which occurs from Senegal to the Arabian Peninsula, is occasionally used as a fodder and may have been taken by Arabian traders to India as fodder for horses, which were one oftheir main trading commodities. Guar was taken to Indonesia, Malaysia, and the Philippines around 1915. It is now grown in many parts of the drier tropics and subtropics. Introduced into the United States in 1903,it was developed into an industrial gum-producing crop during the second World War. Uses Traditionally, the main use of guar is as a green manure and .cover crop, and as a shade plant for ginger and turmeric. Sweet and tender young pods are consumed as a vegetable in northwestern and southern India. They are also eaten as snacks after drying and frying. Mature seeds have been eaten as a pulse during periods of food shortage. Guar is grown as a fresh or dry forage crop and as a feed-grain crop. Guar seed is an important source of the industrial vegetable gum galactomannan, which has a thickening property 5-8 times stronger than starch. It is used as a thickener and stabilizer in foods such as salad dressings, ice cream, yoghurt, tinned vegetables and bakery items, and in the preparation of cheese and reconstituted tobacco. Industrially, guar gum is used to strengthen cloth and paper, as a filtering agent in the mining industry and as an additive to drilling fluids in oil-well drilling. The seedcake, a by-product of guar gum extraction, is an important source ofanimal feed, having a protein content of about 40%. Extracts from guar seed are being tested as a medicine against non-insulin-dependent diabetes and against hyper-cholesteremia. Traditionally, leaves are eaten to cure night blindness, while

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pods are used as a laxative. Production and international trade The main area of production of guar as a green manure and fodder crop is north-western India and Pakistan. The main producers of guar for gum are India, Pakistan and the United States. Limited and fragmented information indicates that the annual production of guar seed in India for the period 1970-1975 was 510 000 t, which increased to 940 000 t in 1976. Pakistan produced 160 000 t in 1974. Annual production in the United States fluctuates strongly, from 35 000 t in 1976 to only 7000 t in 1978, averaging about 15 000 t. In 1987, world trade of guar gum stood at about 125 000 t. The United States is the main importer of guar gum supplied by India and Pakistan and imported about 45 000 t in 1994 at a price of0.5 US$/kg. Properties Green pods contain per 100 g fresh material: water 82 g, protein 4 g, fat 0.2 g, carbohydrates 10 g, fibre 2.5 g, ash 1.5 g, Ca 0.1 g, P 0.25 g, Fe 6 mg, vitamin A 330 IU, vitamin C 50 mg. They contain 40-70 mg hydrocyanic acid per 100 g, which is removed by thorough boiling. The seed consists of 14-16% testa, 38-45(-50)% endosperm and 40-46% cotyledons. Dry seed contains per 100 g: moisture 10 g, protein 30 g, fat 2.5 g, carbohydrates 41 g, crude fibre 13 g, ash 3 g. The proximate composition of guar green forage is per 100 g: moisture 81 g, crude protein 3 g, digestible protein 2.5 g, ether extract 0.4 g, crude fibre 4.4 g, N-free extract 8 g, ash 3.3 g, Ca 0.6 g, P 0.07 g. The galactomannan gum, which makes up 47-68(-85)% of the endosperm, consists of chains of D-mannopyranosyl units to which D-galactopyranosyl units are attached at every second unit. In cold water it forms a gel of exceptionally high viscosity at low concentrations. The viscosity depends on temperature and concentration. Maximum viscosity is achieved at 25-40°C. Viscosity increases proportionally with concentration to about 0.5%. At higher concentrations it increases more slowly. Solutions are stable over a very wide pH range (pH 1-10) and a wide range of salt concentrations. With borate ions hydrated guar gum forms a cohesive, structured gel. Commercial guar gum is 78-82% galactomannan with some protein and other endosperm admixtures. In 1974 the United States Food and Drug Administration affirmed the 'generally recognized as safe status' 4GRAS) ofguar gum, with specific limits. The weight of 1000 seeds is 26-47 g. Description A robust, bushy, erect, annual herb, 20-100 cm tall in improved cultivars, up to 3

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Cyamopsis tetragonoloba (L.) Taubert - 1, flowering and fruiting branch; 2, flower; 3, staminal tube with pistil. m in landraces. Root system well developed laterally. Stems and branches angular, grooved, appressed pubescent with white, forked hairs, sometimes glaucous; some cultivars remain unbranched. Leaves alternate, trifoliolate; leaflets elliptical to ovate, terminal one 8-12 cm long, lateral ones 5-8 cm long; rachis 3-7 cm long, pulvinate; margins toothed, the length ofthe teeth less than 1/10 ofthe breadth ofthe leaflet, which usually exceeds 1 cm. Inflorescence a dense, axillary raceme with 5-30 flowers; flowers up to 9 mm long; calyx hairy, ending in 5 unequal teeth, carinal tooth longest; petals creamy white on emergence, changing through pink to light purple, standard orbicular, wings and keel oblong; stamens 10, filaments united into a staminal tube, anthers apiculate. Pod 6-12-seeded, 4-12cm long, in stiff erect clusters, pubescent or glabrous, straight to slightly curved, beaked, with a single ridge at one suture and two ridges at the other. Seed hard, flinty, flattened, ovoid, about 5 mm long, white, grey or black. Seedling with epigeal germination.

Growth and development After germination, about 3 simple leaves emerge, followed by compound leaves. Under controlled conditions, short daylength and high temperature delay the appearance of trifoliolate leaves and flowering may start before the first compound leaf appears. In branching cultivars most of the initial branching takes place near the stem base. Non-branching types have larger leaves than branched ones. Guar is a quantitative short-day plant, but cultivars in which flowering is not affected by daylength have been developed. Profuse and continuous flowering may start about one month after establishment. Flowers are cleistogamous, but in some cultivars natural crossing maybe as high as 9%.Podformation starts 45-55 days after sowing and peaks after 75-80 days. Seeds ripen 110-160 days after sowing. Guar produces clusters of nitrogen-fixing nodules with Bradyrhizobium strains. Nodulation may start early, the first nodules becoming visible 1 week after germination. Other botanical information Cyamopsis DC. is a small genus of3 species and is closely related to the genus Indigofera L. All species have a diploid chromosome number of 14. The 2 wild species are African (C. serrata Schinz) or mainly African (C. senegalensis). Numerous cultivars of guar have been developed. In general, branched types are more suitable for seed production, while erect, single-stem types that produce larger and more fleshy pods are preferred in vegetable production. In India three main types are sometimes recognized: 'Deshi', a mostly rainfed seed crop, 1.2-1.5 m tall; 'Pardeshi', mainly grown for its green pods, 1.5-1.8 m tall; and 'Sotiaguvar', mostly grown for fodder and green manure, 2.5-3.5 m tall. 'Sofia' is a multipurpose cultivar from Gujarat, grown as a green manure and shade plant and for its green pods,'Durgapura Safed' is a successful cultivar for forage and grain production. 'Brooks' was the first cultivar released in the United States, moderately resistant to the main diseases (Alternaria leaf spot and bacterial blight). However, its resistance to bacterial blight tends to break down under heavy infestation, as is the case with 'Kinman' released in 1974.'Mills' (early maturing), 'Esser' (late maturing) and 'Hall' (full season) were released inbetween 1965 and 1975, 'Lewis' (intermediate) and 'Santa Cruz' (full season) in 1985. These are all higher yielding than older cultivars and were more resistant tobacterial blight when released. The American cultivars and 'Pusa Sadabahar' and

CYAMOPSIS

'Pusa Naubahar' from India are daylength neutral; most other cultivars are photosensitive. Ecology Guar is a hardy, drought-tolerant legume. It grows in a wide range of environments from the sub-humid to semi-arid conditions in the tropics and subtropics with (300-)500-800(-1500) mm of rainfall. The main production of guar for seed occurs where annual rainfall is less than 800 mm. In areas with higher rainfall, vegetative growth is greater, but seed quality is inferior, making guar more suitable as a green manure and fodder crop. Guar prefers a very hot climate. Mean monthly maxima in northern India may reach 35-40°C, though in southern India extremes are lower. Optimum soil temperature for root development is 25-30°C. Guar is cultivated up to 900 m altitude. It is highly susceptible to frost. The optimum temperature for germination is about 30°C. At 20°C, germination is retarded, at still lower temperatures the rate ofgermination is reduced. It can grow in most soils, but thrives in well-drained alluvial and sandy-loam soils of pH 7.0-8.0. Waterlogging is not tolerated. On heavy soils, guar should be grown on ridges to maintain root aeration. In an experiment using irrigation water with equal amounts of NaCl and CaCl 2 , salinity levels up to 8.8 dS/m did not affect germination, early growth or grain yields. Propagation and planting Guar is propagated by seed. Scarifying the seed by mechanical means or by treating it with sulphuric acid tends to give more rapid and more uniform germination. However, under humid conditions germination is generally good without scarification. For green manure production, seed is broadcast at a rate of 35-45 kg in India, versus 22-35 kg/ha in the United States. In northern India, vegetable guar is generally grown twice per year, the first crop is sown after the start ofthe rainy season in June-July, the second crop is sown in February-March at the start of the hot season, and is grown under irrigation. In southern India, vegetable guar is grown throughout the year. In vegetable production, seeds are generally sown in raised beds, 5-7 cm deep at 45-60 cm x 22-30 cm or dibbled at 60 cm x 30-60 cm. The seed rate used ranges from 3-12 kg per ha. For grain production in India, sowing is done in March-April under irrigation, while rainfed guar is sown soon after the onset of the monsoon rains in June-July. Seed is often broadcast, though sowing in rows gives higher yields. Spacing between rows varies from 30-60 cm, within-row spacing

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from 15-30 cm. Seed rates range from 10-15 kg/ha, but 12-25 kg/ha is also reported. For grain production in the United States, guar is sown in rows 60 cm or 90-110 cm apart, at 10-30 cm within rows, using seed rates of 4-7 kg/ha. The recommended depth of sowing is 2.5-5 cm. Differences in seed rates reflect cultivar type and growing conditions rather than seed size. Guar responds well to inoculation with rhizobium, which can improve nodulation by as much as 36%. Group E (cowpea) or Group PE inoculant are as good as specific guar inoculants. Husbandry In India, especially in dry areas, such as Gujarat, guar is often grown as an intercrop with other annuals such as pearl millet, sorghum, maize or cotton. It is also grown as a cover crop between young rubber or young coconut trees. As a sole crop it is grown in rotation with maize, sorghum, cotton, wheat and vegetables. Guar plants cannot withstand much weed competition and inter-row weeding by chemical or mechanical means is needed. At least 2 mechanical weedings are normally required. In the United States the application ofpre-emergence herbicides is recommended. Trifluralin and profluralin have been found to be non-toxic to guar. Alternatively, EPTC, chlorthal, naptalam or linuron can be used. Precautions should be taken if these herbicides are to be used when intercropping is practised. When grown as a vegetable, weeding is done manually. The fertilizer requirements of guar are dependent on soil fertility. On fertile soils or soils well-fertilized in the previous season, guar hardly responds to fertilizer application. Otherwise, application of 30-50 kg/ha ofP 2 0 5 and 10-15 kg/ha ofK 2 0 is recommended. Although guar is adapted to rainfed agriculture, it responds well to irrigation. It has the ability to cease growth during dry weather and to sprout when rain resumes. Diseases and pests Internationally, bacterial blight, caused by Xanthomonas cyamopsidis and leaf spot caused by the fungus Alternaria cucumerina var. cyamopsidis are the main diseases of guar. Bacterial blight is seed-borne and infected seedlings are often killed rapidly. In older plants the disease develops from transparent, oily leaf spots coalescing into brown, angular, necrotic lesions. Infection spreads systemically throughout the plant and can kill it at any stage of development. The cultivars 'Brooks', 'Hall', and 'Mills', which were originally resistant, are now affected by a highly virulent strain. Soaking the seed in

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hot water at 56°C for 10 minutes will eliminate seed-borne infection. Alternaria leaf spot develops between flowering and pod set. It causes defoliation, especially during periods of high rainfall and humidity. Dithane and cupramar give excellent control of this disease. A mildew, caused by Oidiopsis taurica, is widespread and causes some damage, especially during periods of humid weather. Guar is relatively free of pests. The midge Contarinia texana causes damage in the United States and has caused yield losses of 20-30%. Effective, economical chemical control is possible. A gall midge (Asphondilia sp.) occurs in India and the United States and may cause limited damage late in the growing season. Harvesting The best time for harvesting guar for fodder is during flowering and early pod formation. In India pods are often picked for home consumption before the fodder is harvested. In some regions guar is grazed, usually after frost, to reduce the risk of bloat in ruminants. It takes about 4-6 weeks from the onset of natural defoliation for guar to dry sufficiently to allow mechanical harvesting. The pods of most cultivars do not shatter. Moist conditions during this stage may cause the seed to weather and blacken. In India most harvesting is done manually and often starts when the stalks are still green. Subsequently, the plants are put in loose stacks, for rapid drying. This system avoids weathering of the seed, but harvesting too early will reduce the yield and the gum content. In the United States frost often kills the maturing crop, initiating rapid drying. Alternatively, desiccants such as paraquat may be used to promote drying. Harvesting is carried out with an adjusted standard combine harvester. When grown for green pods, harvesting occurs 50-80 days after sowing, with the tender pods being picked every 2-3 days for several weeks. Yield As a rainfed forage or green manure crop, average yields in India are 8-12 t/ha, 10-12 weeks after sowing. Under irrigation, average yields are 16-20 t/ha. A green manure crop adds about 50 kg fixed nitrogen to the soil. Yield increments of crops following guar can be very high. Increases in wheat yield of 1500 kg/ha on light soils and 500 kg/ha on heavy soils are reported from India, while yield increases in cotton from 450-540 kg/ha are reported. In an experiment in the United States barley yield increased from 3.2 t/ha to 5.1 t/ha, 0.8 t/ha more than after other green manure crops. Dry grain yield under rainfed conditions in India

and the United States ranges from 350-1000 kg/ha, depending on rainfall and time of sowing. Under experimental conditions it rarely exceeds 1300 kg/ha. Yield can be more than doubled under irrigation. Under experimental conditions in the United States yields of over 3 t/ha have been obtained with 'Kinman' and 'Esser', in Zimbabwe over 3.5 t/ha with 'Mills' and 'Hall'. Average yield of green pods is about 2000 kg/ha for a premonsoon crop and 2500-3000 kg/ha for a monsoon crop. Experimentally, yields of over 9000 kg/ha have been obtained with 'Pusa Mausami'. Handling after harvest Guar gum is prepared from the seed by dry milling. In a multi-stage grinding and sifting process, the testa and cotyledons are removed to obtain 'splits'. Food-grade guar gum is made by grinding splits to a fine particle size. Most seed is milled to guar gum in the country of production. Guar gum can be purified by autoclaving a mixture of the gum in water to obtain a 0.8% dispersion, followed by gradual addition of ethanol to a concentration of 40% and repeated centrifugation to precipitate the pure galactomannan. The purified gum can be chemically changed to adjust its gel-making and water-binding characteristics to specific applications. Genetic resources The National Bureau of Plant Genetic Resources, New Delhi, India and the Agricultural Research Institute, Lyallpur, Pakistan have representative collections of guar accessions. In the United States, the Texas Agricultural Experiment Station, Vernon, Texas and the Oklahoma State University, Stillwater, Oklahoma maintain collections. In addition to these actively used collections, the entire plant collection of 1300 accessions of 33 cultivars and local forms is stored at the National Seed Storage Laboratory, Fort Collins, Colorado. Breeding Selection and breeding in guar in the United States aims at increased seed production and disease resistance, while in India cultivars have been selected for seed, vegetable, and multipurpose use. The American cultivars are derived from a very small number of introductions from India, leaving the genetic variability largely unutilized. An improved technique for controlled pollination of guar has been developed in India. Male sterility has been found, with pollen fertility probably being monogenically dominant over sterility. Recent research has concentrated heavily on increasing grain yield. This was justified by the strong and growing market for guar gum and the

DACTYLADENIA

increasing number of its applications. Development of determined cultivars with a compressed flowering phase and improved tolerance of temporary waterlogging have been suggested to increase its adaptability. Despite the crop's good prospects, research on guar all but stopped in the United States around 1985. Prospects Although a few improved multipurpose cultivars have been developed in India, few efforts have been made to develop the green manure, cover crop, vegetable and forage aspects. These aspects would be most important in the drier parts of South-East Asia. There, it could become more important, being one of the few green manure and cover crops providing a useful byproduct. Development of disease tolerance under humid conditions and agronomic research to incorporate it in a wider range of crop production systems would be urgently required. Literature 111 Arayangkoon, T., Schomberg, H.H. & Weaver, R.W., 1990. Nodulation and N 2 fixation of guar at high root temperature. Plant and Soil 126: 209-213. 121 Beech, D.F., Stutzel, H. & Charles-Edwards, D.A., 1989. Yield determinants of guar. 1. Grain yield and pod number. 2. Nitrogen accumulation and growth at high plant density. Field Crops Research 21: 29-37, 39-47.131 Cave, A., 1995. Pharmacognosy, phytochemistry, medicinal plants. Lavoisier Publishing, Paris, France & Intercept Ltd., Andover, United Kingdom, pp. 93-93. 141 Duke, J.A., 1981.Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 70-73. l5l Francois, L.E., Donovan, T.J. & Maas, E.V., 1990. Salinity effects on emergence, vegetative growth, and seed yield of guar. Agronomy Journal 82: 587-592. 16! Jackson, K.J. &Doughton, J.A., 1982. Guar: a potential industrial crop for the dry tropics of Australia. Journal of the Australian Institute of Agricultural Science 48: 17-32. I7l Kay, D.E., 1979. Food legumes. TPI Crop and Production Digest No 3.Tropical Products Institute, London, United Kingdom, pp. 72-85. I8l Seaman, J.K., 1980. Guar gum. In: Davidson, R.L. (Editor): Handbook of water-soluble gums and resins. McGraw-Hill Book Company, New York, United States, pp. 1-19. 191Whistler, R.L. & Hymowitz, T., 1979. Guar: agronomy, production, industrial use and nutrition. Purdue University Press, West Lafayette, Indiana, United States. 124 pp. L.J. Wong &C. Parmar

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D a c t y l a d e n i a b a r t e r i (Hook.f. e x O l i v e r ) G.T. P r a n c e & F . W h i t e Brittonia 31: 484 (1979). CHRYSOBALANACEAE

2ra=22 Synonyms Griffonia barteri Hook.f. ex Oliver (1871), Acioa barteri (Hook.f. ex Oliver) Engler (1899). Vernacular names Monkey fruit (En). Origin and geographic distribution Dactyladenia barteri is endemic to West and Central Africa from Sierra Leone to Cameroon and Gabon. Its occurrence in Kivu in Zaire is uncertain. Uses D. barteri is widely used in south-eastern Nigeria as a fallow crop, producing large amounts of litter and recycling appreciable quantities of nutrients through its deep root system. The dense canopy also aids in weed suppression. In farmers' fields, it is either planted or protected in natural regrowth. Leaves are used for fodder. Stems provide good quality poles for staking crops and for construction work. In Nigeria and Liberia the bark and roots are used medicinally as a purgative and against a variety of ailments. Properties The leaves of D. barteri grown on acidic sandy soil contain per 100 g oven-dry matter: N 1.7 g, P 0.08 g, K 0.77 g, Ca 0.57 g, Mg 0.25 g, Cu 1.2 mg, Zn 0.8 mg. The dark red wood of D. barteri is hard and durable and resistant to termite attack. Botany Climbing shrub or small tree, up to 12 m tall; bole fluted, often multiple, crooked, up to 25(-40) cm in diameter; bark brittle, slash thin and watery-white, turning reddish; crown dense, spreading. Young shoots dark red, covered with whitish, arachnoid tomentum, early caducous; branches more or less scandent, slender, hispid, very quickly glabrescent when young, with numerous lenticels when old. Leaves alternate, simple; stipules often attached near the base of the petiole, linear, 4-6 mm long; petiole 3-4 mm long; blade elliptical-oblong to ovate, 7-13(-15) cm x 3-5.5(-7) cm, dark glossy green, turning reddishbrown when senescent, base acuminate, sometimes broadly acuminate and somewhat asymmetrical, apex acuminate; lateral veins in 4-6 pairs, some circular glands often present on the underside ofthe blade near the base and the apex. Inflorescence a terminal or axillary raceme, single or sometimes in pairs, 3-4(-12) cm long, puberulous, many flowered; peduncle up to l(-4) cm long; bracts elliptical-lanceolate, 2-4 mm long, tricuspi-

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Dactyladenia barteri (Hook.f. ex Oliver) G.T. Prance &F. White - 1, flowering branch; 2, flower; 3, section through flower; 4, fruit. date, often with circular glands; pedicel articulated, portion below articulation 6-10 mm long, long persistent, bearing 2 alternate, lanceolate bracteoles 1-1.5 mm long; upper portion 5-15 mm long; flowers bisexual, zygomorphic; receptacle tubular, 4-6 mm long, puberulous; sepals 5, 4-5 mm long, puberulous outside; petals 5, oblong-obovoid, 4-5 mm long, white, caducous; stamens 15-20, (15-)25(-30) mm long, ligulately connate for most of their length, far exserted; pistil with 1-locular ovary, a filiform style slightly longer than the stamens, and a 3-lobed stigma. Fruit a single-seeded drupe, compressed-ovoid, 2.5 cm x 3.5 cm x 5.0 cm, green, surface often ferruginous-tomentose, apex often slightly tuberculate. Seedling with epigeal germination. The root system is deep, but its lateral expansion in the top layer ofthe soil is limited. On an ultisol in south-eastern Nigeria, for instance, about 50% of the roots of less than 2 mm in diameter occurred in the top 20 cm of the soil near the stem, whereas at a distance of 120 cm from the tree base this percentage dropped sharply. In Nigeria and

Ghana, D. barteri flowers usually during the dry season, between October and February. Fruits mature at the beginning of the rainy season, between March and May. D. barteri is open-pollinated, the main pollinators being red ants. Ecology D. barteri occurs in lowland forest up to 300 m altitude with at least 1200 mm rainfall per year, where the mean minimum temperature ofthe coldest month is about 20°C and mean maximum temperature of the hottest month about 34°C. In the forest-savanna transition zone, it is found along river banks, sometimes on the inland side of mangrove forest. It is well-adapted to leached, acid and infertile soils and can survive occasional flooding. Established trees are fire-resistant. Agronomy Propagation is mainly by seed. Occasionally, stakes are used as cuttings in live fence systems. Juvenile stem cuttings will also root quickly. Seed germinates readily. It can be stored for up to 6 months at 15°C when treated with copper sulphate. Direct sowing is possible, but seedlings survive better when raised in nursery bags before planting out. In traditional cropping systems, D. barteri is retained, planted scattered, or in hedgerows. Established trees coppice well, even after pollarding or burning. In southeastern Nigeria it is planted in hedgerows in a traditional alley cropping system with interhedgerow spacing of 2-3 m in fallow systems with 1-2 years of cropping followed by 3-4 years of fallow. Following the fallow period, the shrubs are underbrushed and burned and stems cut to a height of 10-20 cm. Some stems are left uncut for live staking of white yam {Dioscorea rotundata Poiret). Crops are then interplanted in the alleys. Planted at 4 m x 4 m spacing, D. barteri can produce per ha 6 t dry prunings (leaves and small branches), 4 t twigs and 9 t wood within 8 months, with a nutrient yield of the prunings of 85 kg N, 5 kg P, 43 kg K, 18 kg Ca and 46 kg Mg. In an alleycropping experiment, D. barteri planted in rows 4 m apart at a within-row spacing of 50 cm produced 3.5 t/ha oven-dry litter and 1.4 t/ha dry wood when pruned 22 months after planting. The nutrient content of the prunings was: 65 kg N, 6 kg P, 41 kg K, 33 kg Ca and 13 kg Mg. The prunings have a high C/N ratio (28:1 - 36:1), lignin (47.6%) and polyphenols (4.1%) content and decompose slowly in the soil, making good mulch material. The mulch has little direct effect on soil nitrogen. Nitrogen immobilization by decomposing D. barteri leaves is counteracted by increased mineralization of soil organic matter under the

DERRIS

mulch. The decomposition rate of the mulch is very low. After 100 days as little as 20% may have decomposed, after 6 months about 50%. Genetic resources and breeding The genus Dactyladenia Welwitsch comprises about 27 species. It has been suggested that D. lehmbachii (Engl.) Prance & F. White and D. pallescens (Baill.) Prance & F. White, which flower in the same period, may cross-pollinate with D. barteri. There is potential for genetic improvement of D. barteri to enhance coppicing, growth and biomass yield. Prospects D. barteri has shown promise as a mulch and alley crop in experiments at the International Institute of Tropical Agriculture (UTA) in Nigeria. There is a need to evaluate its potential in other regions of the tropics with high rainfall and acid soils, in agroforestry systems to promote sustained crop production on highly weathered soils.Already in use at the IITA as a test tree in alley cropping systems on poor acid soils, it may contribute to the development of such systems in South-East Asia as well. Provenance evaluation and variability studies are needed to reveal the amount of exploitable genetic variation which may exist within D. barteri. Literature 111 Kang, B.T., Akinnifesi, F.K. & Pleysier, J.L., 1994. Effect of agroforestry woody species on earthworm activity and physicochemical properties of worm casts. Biology and Fertility of Soils 18: 193-199. I2l Kang, B.T., Versteeg, M.N., Osiname, O. & Gichuru, M.P., 1991. Agroforestry in Africa's humid tropics: three success stories. Agroforestry Today 3:4-6. 131 Letouzey, R. & White, F., 1978. Chrysobalanaceae. In: Aubréville, A. & Leroy, J.F. (Editors): Flore du Cameroun. Vol. 20. Muséum National d'Histoire Naturelle, Paris, France, pp. 10-13. I4l Hauser, S., 1993. Root distribution of Dactyladenia (Acioa) barteri and Senna (Cassia) siamea in alley cropping on ultisol. 1. Implication for field experimentation. Agroforestry Systems 24: 111-121. l5l Kachaka, B., Vanlauwe, B. & Merckx, R., 1993. Decomposition and nitrogen mineralization of prunings of different quality. In: Mulongoy, K. & Merckx, R. (Editors): Soil organic matter dynamics and sustainability oftropical agriculture. John Wiley and Sons, Chichester, United Kingdom, pp. 199-208. 16!Ruhigwa, B.A., Gichuru, M.P., Mambani, B. &Tariah, N.M., 1992. Root distribution of Acioa barteri, Alchornia cordifolia, Cassia siamea and Gmelina arborea in an acid ultisol. Agroforestry Systems 19: 67-78. 171 Tian, G., Kang, B.T. & Brussaard, L., 1992. Biological effects of

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plant residues with contrasting chemical compositions under humid tropical conditions - decomposition and nutrient release. Soil Biology and Biochemistry 24: 1051-1060. D.O. Ladipo &B.T. Kang

Derris m i c r o p h y l l a (Miquel) B.D. Jackson Index kewensis 1:332 (1893). LEGUMINOSAE - PAPILIONOIDEAE

2n =unknown Synonyms Brachypterum microphyllum Miquel (1861), Derris dalbergioides Baker (1878), Deguelia microphylla (Miquel) Valeton (1904). Vernacular n a m e s Vetch tree (En). Indonesia: kayu retak (Palembang). Malaysia: daun berayai, batai, betek (Peninsular). Thailand: khangten (south-eastern), di-ngu, fantae (peninsular). Origin and geographic distribution D. microphylla occurs naturally in Sumatra, Peninsular Malaysia, Thailand, Burma (Myanmar) and possibly in Indo-China. Its natural occurrence in Java, where it is often planted, is uncertain. Uses In Java, D. microphylla is occasionally grown as a shade tree in cocoa, coffee and tea plantations especially on poor soils. It is also used as green manure. The wood is used as building material and as firewood. In Malaysia a poultice of roots or bark is used to treat itch. Its abundant purple flowers make it a distinctive ornamental tree. Properties Many Derris species contain rotenone and related compounds, which have insecticidal and piscicidal properties. It is unlikely that D. microphylla contains exploitable quantities of these compounds. All parts produce a foetid smell when crushed. Botany Tree with several ascending branches and umbrella-shaped, feathery crown, 5-20 m tall; bark light-grey to brown, slightly fissured. Branchlets, petioles and buds golden-brown silky, glabrescent. Leaves imparipinnate, petiole and rachis 9-20 cm long; petiolule 1-2 mm long; leaflets 19-43, elliptical-oblong, 1.5-3.2 cm x 0.81.2 cm, rounded-emarginate at both ends, both surfaces thinly appressed brown hairy, glaucous below. Inflorescence an axillary raceme, 2-13 cm long, 1-3 together; flowers 7-8 mm long; pedicel 0.5-1.5 cm long; calyx campanulate; corolla darkred to violet; standard 9 mm x 7 mm, bearing 2 glands at base; stamens 10, monadelphous, 1 stamen free at top and bottom but adnate to stamen

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mended planting distance is about 3 m x 3 m, gradually thinned out to a final spacing after 10 years of 10 m x 10 m. Experiences with D. microphylla grown as a shade tree in tree crops are mixed. Early reports, especially from tea plantations, indicate positive results, later reports from coffee and cocoa plantations draw attention to its slower growth, more superficial root system and lower production of organic matter resulting in poorer growth of the main crop than is the case with shade trees like Paraserianthes falcataria and Erythrina subumbrans (Hassk.) Merrill. However, it requires little maintenance, and pruning and pollarding are well tolerated. D. microphylla is attacked by the fungi Ganoderma pseudoferreum, Rosellinia and Ustulina zonata which affect its root system, and by several bagworm species. It is resistant to most borers. In the mid 1940s large numbers of trees died in West Java of unknown causes.

Derris microphylla (Miguel) B.D. Jackson - 1, flowering branch; 2,flower; 3,pod; 4, seed. tube in centre. Pod flat, in outline elliptical to linear-lanceolate, 2.5-7 cm x 1.2-1.7 cm, l-2(-5)seeded, indéhiscent, narrowed at both ends, glabrous to puberulous, leaf-like along dorsal suture with a 1-2 mm wide wing. Seed 6 mm x 3 mm, brown-green. D. microphylla does not grow very fast and does not produce large amounts of green matter. The root system, which is superficial, produces large numbers of root nodules and, when damaged, large numbers of saplings. In Java, D. microphylla flowers in August-January. D. microphylla is classified in section Brachypterum (Wight &Arnott) Benth. ofthe genus Derris Lour.; this section is sometimes considered a separate genus and in that case the correct name of the species is Brachypterum microphyllum Miquel. Ecology In Java and Peninsular Malaysia, D. microphylla occurs from 200-1200 m altitude. It is tolerant of strong winds. To provide shade in plantations it is mostly planted on soils too poor for Leucaena leucocephala (Lamk) de Wit or Paraserianthes falcataria (L.) Nielsen. Agronomy Propagation by seed and by cuttings is easy. For firewood and timber use the recom-

D. microphylla is a suitable tree for filling in gaps for soil protection in mature tree plantations, where it is easier to establish than most other trees. Genetic resources and breeding A small collection of Derris germplasm including material of D. microphylla is being maintained at the National Germplasm Repository, Miami, United States. Prospects D. microphylla may continue to play a role as a shade tree in tree crops on poor soils. On more fertile soils Paraserianthes falcataria and Leucaena leucocephala generally give better results. It remains a useful tree for filling in gaps in plantations, where it is difficult to establish other trees. Literature 111 Backer C.A. &van Slooten, D.F., 1924. Geïllustreerd handboek van de Javaansche theeonkruiden en hunne betekenis voor de cultuur [Illustrated handbook of weeds of Javanese tea plantations and their significance for tea-growing]. Ruygrok, Batavia, Dutch East Indies, p. 147, 147a. 121 Polhill, R.M., 1971.Some observations on the generic limits in Dalbergieae-Lonchocarpinae. Kew Bulletin 25:259-273. I3l Schoorel, A.F., 1949. Handleiding voor de theecultuur [Manual of tea cultivation]. De Centrale Vereniging tot Beheer van Proefstations voor de overjarige Cultures in Indonesië. Veenman, Wageningen, the Netherlands, pp. 133-134. 141 Valeton, T., 1906. Deguelia microphylla Miq. In: Koorders, S.H. &Valeton, T. (Editors): Icônes bogorienses. Vol. 2, t. 129, pp. 141-142. 151Whitmore, T.C. & Ng, F.S.P., 1983. Tree Flora of Malaya: a manual for foresters. 2nd edition, Vol. 1. Malayan Forest Records No 26.

DESMODIUM

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Forest Research Institute of Malaysia, Longman Malaysia, Sendirian Berhad, Kuala Lumpur, Malaysia, pp. 290-291. K. Thothathri & Rugayah

D e s m o d i u m a d s c e n d e n s (Swartz) DC. Prodr. 2:332(1825). LEGUMINOSAE - PAPILIONOIDEAE

2« = 22 Synonyms Hedysarum adscendens Swartz (1788), Desmodium oxalidifolium G. Don (1832), D. trifoliastrum Miquel (1855). Vernacular names Tick clover, sweetheart (Dominica), adscendens (South America) (En). Zarzabacoa galana (Am). Philippines: pega pega. Vietnam: bai ngai. Origin and geographic distribution D. adscendens occurs naturally in tropical Africa and South America. It has been introduced throughout South and South-East Asia and Melanesia. Uses In South-East Asia and tropical Africa, D. adscendens is used as cover crop in tea, coffee and oil-palm plantations. In Zanzibar and mainland Tanzania it is used as a cover crop in clove plantations and has been tested as a forage legume in coconut stands. In Brazil, it provides forage for all stock, especially for horses. In Dominica in the Caribbean it is said to provide a useful medicine against gonorrhoea, in Zaire against stomachache. Properties In Brazilian analyses the composition of 100 g dry matter was: crude protein 10.5 g, ether extract 3.4 g, nitrogen free extract 49.8 g, crude fibre 31.4 g, Ca 0.92 g, and P 0.13 g. The digestibility of organic matter was 64.9%. When harvested at mid-bloom stage, the composition of 100 g dry matter was: crude protein 14.7 g, ether extract 2.7 g, nitrogen free extract 39.7 g, crude fibre 34.8 g. The estimated digestible protein content was 2.5-2.7 g, the energy value 2200-2300 kJ/kg. Botany A creeping or ascending perennial herb or low shrub, up to 1m long, taproot diffuse. Stem terete, often rooting near the base, striate, densely soft hairy, glabrescent. Leaves trifoliolate; stipules obliquely ovate-lanceolate with long attenuate apex, up to 1 cm x 3 mm, persistent; petiole 1-3 cm long, rachis up to 1 cm long, both pilose; leaflets elliptical-obovate, terminal leaflet (1.5-) 2-4(-5.5) cm x 1-3 cm, lateral leaflets smaller, cuneate to rounded at base, margin entire, obtuse and emarginate at apex, upper surface glabrous to

Desmodium adscendens (Swartz) DC. - 1, habit of flowering and fruiting plant-part; 2, pod. sparsely pubescent, lower surface sparsely to densely soft pilose, lateral nerves rather distinct and not reaching the margin, 4-7 on either side of the midrib. Inflorescence a terminal or axillary raceme, 4-20 cm long, lax-flowered; flowers usually in pairs; bracts ovate with a long-acuminate apex, 4 - 6 ( - l l ) mm x 1.5-2.5 mm, densely pubescent, early caducous; pedicel slender, up to 2 cm long in fruit, densely covered with mixed, spreading, hooked and straight hairs less than 1 mm long; bracteoles absent; calyx 2.5-3.0 mm long, covered with persistent, patent, long hairs especially on the 5 teeth and with minute straight or hooked hairs; corolla white or purple to violet; standard broadly obovate or orbicular, 4.5-5.5 mm x 4.0-4.5 mm, rounded or refuse at the apex, shortly clawed; wings nearly obovate, about 4 mm x 2 mm, obtuse at the apex, auriculate at the base, shortly clawed; keel-petals 4.5-5.0 mm long, incurved, subacute at the apex, distinctly longclawed, claw 2-3 mm long; stamens diadelphous; pistil 5.0-5.5 mm long, densely short-hairy on the ovary, style glabrous, stigma minutely capitate.

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Pod narrowly oblong, 1.0-2.5 cm x 3-4 mm, 3-6jointed, dehiscent along the lower sutures, rarely shortly (1-2 mm) stipitate, slightly swollen on the seed, densely covered with very short, spreading, hooked hairs. Seed flattened, ellipsoid, 2.5-5.0 mm x 1.5 mm. Several varieties and forms have been distinguished in the taxonomie literature on the basis of size and thickness of leaflets and on degree of hairiness. Because many intermediate forms occur as well, D. adscendens is best considered as a rather variable species, of which the extreme forms do not deserve separate taxonomie recognition. Ecology D. ascendens occurs in damp swamp forest and other humid, locations like stream banks and bunds of rice fields, provided that they are shady. In equatorial regions it is found from 200-1000 m altitude. In Java, it flowers yearround. In the subtropics it flowers late in the growing season. Agronomy D. adscendens is usually propagated by seed, but propagation by stem cuttings is also possible. Planted at 1 m x 1 m spacing, it forms a permanent ground cover. It loses its leaves after flowering during the dry season, and some stems may die. Growth starts again with the onset of the rains. In Brazil, 3-4 cuts per year can be taken for forage. It has been tested in Colombia, and in Florida it was found to be resistant to root-knot nematodes. Genetic resources and breeding Small numbers of D. adscendens accessions are included in the Desmodium collections of the Centro Agronómico de Agriculture Tropical (CIAT), Colombia and of the United States Department of Agriculture (USDA) in Florida. Prospects D. adscendens may continue to play a role as a green manure and cover crop. Its resistance to root-knot nematodes may prove useful in Desmodium breeding programmes. Literature 111 Backer, CA. & Bakhuizen van den Brink, R.C., 1963. Flora of Java. Vol. 1. Noordhoff, Groningen, the Netherlands, p. 608.121 Bogdan, A.V., 1977. Tropical pasture and forage plants (Grasses and legumes). Longman, London, United Kingdom, p. 341. 131 Kretschmer, A.E., Sonoda, R.M. & Snyder, G.H., 1980. Resistance of Desmodium heterocarpon and other tropical legumes to root-knot nematodes. Tropical Grasslands 14: 115-120. 141 Ohashi, EL, 1973.The Asiatic species of Desmodium and its allied genera (Leguminosae). Ginkgoana 1: 199-203. 151 Schubert, B.G., 1971. Desmodium. In: Milne-Redhead,

E. & Polhill, R.M. (Editors): Flora of tropical East Africa. Leguminosae (Part 3), Papilionoideae (Part 1). Crown Agents for Oversea Governments and Administrations, London, United Kingdom, pp. 461-462. 161 Whyte, R.O., Nilsson-Leissner, G. & Trumble, H.C., 1953. Legumes in agriculture. FAO, Rome, Italy, p. 269. C.C.Wong &P.K. Eng

E i c h h o r n i a crassipes (Martius) Solms A. D C , Mon. Phan. 4: 527 (1883). PONTEDERIACEAE

2n = 32 Synonyms Pontederia crassipes Martius (1823), Eichhornia speciosa Kunth (1843). Vernacular n a m e s Water hyacinth (En). Jacinthe d'eau (Fr). Indonesia: eceng gondok (general, Sundanese), kembang bopong (Javanese), kelipuk (Palembang). Malaysia: keladi bunting, kemeling telur, bunga jamban. Philippines: water lily. Burma (Myanmar): beda-bin, ye-padauk. Cambodia: kâmplaôk. Laos: tôb po:ng. Thailand: phaktop-chawa. Vietnam: l[uj]c b[if]nh, b[ef]o nh[aaj]t b[ar]n. Origin and geographic distribution Water hyacinth is native to tropical South America. During the latter half of the 19th Century it spread beyond its original habitat as an ornamental and subsequently became naturalized in tropical and subtropical areas around the world. It was first introduced into South-East Asia in 1894 to the Bogor Botanical Garden in Java, from where it spread over the Indonesian Archipelago. It was introduced into Singapore from Hong Kong in 1903 by the Chinese. The plant arrived in the Philippines in 1912. From Bangkok, where it was introduced from Java, water hyacinth spread over the Chao Phraya delta and along the Mekong river and adjacent regions in Vietnam, Cambodia and Laos, where it was already causing concern in 1908. Water hyacinth was first reported from Papua New Guinea in 1962. U s e s Water hyacinth is considered one of the world's most troublesome weeds because of its rapid growth and formation of dense, impenetrable mats of vegetation which hinder navigation and fishing, obstruct irrigation and drainage of farm land and crowd out other plants. To decrease the costs of water hyacinth control and the negative effects of chemical control, various studies have been carried out on possible ways of using it. However, it is difficult to harvest and process

ElCHHORNIA

large masses with a very high water content (90-96%) in an economical way. The simplest and most practical routine use of water hyacinth is as green manure, compost and mulch for soil improvement. It is sometimes used as a fodder, and in South and South-East Asia it is common to see water buffaloes grazing it. It is further used in fish traps, where fish are trapped in nets under small clusters of water hyacinth, and to produce paper and biogas by means of anaerobic fermentation. In biogas production the high moisture content in the plants is an advantage, because moisture is needed for the fermentation process. One hectare of water hyacinth produces about 70 000 m 3 of biogas, one kg of dry material producing about 370 1.Increasing attention is being given to its potential as a water-clearing agent. The roots trap large amounts of dispersed organic and inorganic particles and efficiently remove minerals, including several heavy metals and radio-active elements. The feasibility of using water hyacinth as a substrate for mushroom cultivation is being studied. In some countries in the temperate zones water hyacinth is cultivated as an indoor plant. In Indonesia a home industry has been established producing handicrafts such as lady handbags, slippers, hats, and vests from the elongated dried petioles ofwater hyacinth. Properties The different organic constituents in water hyacinth are nutritionally comparable to those of any other forage. The protein content varies from 7.4-18.1% on a dry weight basis. The concentration of the basic elements is in the same range as in terrestrial forage plants whereas those of iron, sodium, potassium and calcium are relatively high. Per 100 g dry matter the proximate composition is: Fe 0.3 g, Na 0.4 g, K 4.6 g, Ca 1.3 g. The nitrogen and phosphorous concentration as well as the concentrations of heavy metals are directly correlated with the concentrations in the water. It is advisable to mix water hyacinth with other fodders, because it can contain high levels of K and CIand its P levels are often inadequate. Description Perennial herb, 30-60 cm tall, rarely taller, floating free or rooting in the mud of shallow waters. Root system mainly composed of adventitious roots (blackish with age) originating from the rhizome and bearing many laterals; rhizome consisting of several nodes and internodes, each node with a leaf, and emitting stolons. Leaves consist of a petiole, a thin part between petiole and blade, called isthmus, and a blade; petiole elongated (when plants are rooted in the soil or growing in dense stands) or forming a bul-

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Eichhornia crassipes (Martius) Solms - habit of flowering plant. bous float; blade broadly ovate or rhomboid with an almost cordate base. Inflorescence a long-peduncled, axillary spike subtended by two bracts, with 5-35 spirally arranged flowers, usually simultaneously expanding and withering; flowers zygomorphic, with a perianth of 6 pale-purple segments; the posterior segment largest, about 3 cm long, with a bright yellow, blue-bordered median blotch; stamens 6, variable in length; ovary superior, conical, trilocular with numerous ovules, style terminated by an almost capitate stigma at medium height between the anthers of long and short filaments. Fruit a dehiscent capsule containing a variable number of seeds. Seed ovoid, 1 mm x 0.5 mm, ribbed. Growth and development Propagation is mainly by vegetative means, i.e. through stolons. Only where it occurs in seasonally dry habitats is multiplication by seed important. Under favourable conditions growth is very rapid. The area under plant cover may double within a period of 6-15 days. In general, water hyacinth flowers profusely, both under long- and short-day conditions. Flowers of water hyacinth are tristylous, the most common form, also in South-East Asia,

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has 3 long and 3 short stamens and an intermediate style. Other forms, which are mostly absent outside the Amazon basin, have either 3 long and 3 intermediate stamens and a short style or a long style and 3 intermediate and 3 short stamens. In the natural habitat, pollination is carried out by pollen-collecting and nectar-collecting bees. Most effective pollination occurs between flowers of different style length, but fertilization by pollen from the same form occasionally occurs. In areas where water hyacinth has been introduced, pollinators are generally absent and some self-pollination may occur. In South-East Asia fruits are seldom produced if pollination is not carried out artificially. The fruits usually mature under water and in general a period of 20 days is necessary for the production of ripe seed. When the fruit bursts upon maturity, seeds will sink to the bottom of the water. The seed-coat acts as a physical barrier to germination. However, if the seed-coat is cracked, for example by alternate drying and wetting, germination may occur soon after shedding. On the other hand, there are reports of seeds remaining dormant for a period of about 20 years. Seedlings produce 2-3 ligulate leaves in 10 days and 7-8 ligulate plus 1-3 spatulate leaves in 30 days. Ecology Water hyacinth thrives in various fresh-water habitats, ranging from shallow ponds, marshes, and small streams to large lakes and rivers. However, strong wave movements will unfavourably affect its growth. When ponds or floodplains dry out, water hyacinth dies rapidly. It is heliophilous and grows best under high light intensity. The present geographic distribution ranges from the Equator to nearly 38°N and 38°S which demonstrates its tolerance of various temperature regimes. Air temperatures may be as low as 1°C and as high as 40°C. Leaves are killed by frost, but plants survive until the rhizomes are frozen. Water hyacinth occurs in water having a wide range of pH values, but dense vegetations are mainly found in water with a pH near 7. Although the chemical composition ofthe water may vary to a large extent, the salt tolerance of water hyacinth is relatively low. Diseases and pests In general, water hyacinth is very little affected by diseases and pests outside its natural habitat. However, fungi and arthropods that can be used as biological means of weed control have been identified. Of the few host-specific virulent pathogens, only the fungus Cercospora rodmanii, a native of Florida, has been found suitable for large-scale field application. Various

arthropods have been collected in its original habitat in South America and the most promising agents for biological control are the curculionid weevils Neochetina eichhorniae and N. bruchi, and the stem-boring pyralid moth Sameodes albiguttalis. These insects have already been put to practical use and have become established in new habitats following their introduction. They cannot control water hyacinth by themselves, so additional control measures remain needed. Apart from the above-mentioned biological means of control, water hyacinth can be removed physically (manually or mechanically) or killed with herbicides. It should be taken into consideration that chemical control may bring about risks to the environment. The herbicide most commonly used against water hyacinth is 2,4-D (2-5 kg/ha). Genetic resources and breeding No substantial germplasm collections are known to be maintained. Prospects Water hyacinth is the subject of extensive research, which bodes well for the development of new applications. Its operational use in the treatment ofwaste water including sewage effluent, removing both dispersed particles and heavy metals is likely to develop further. Attempts are also being made to combine the water treatment potential of water hyacinth with biogas production. Its role as a green manure, mulch and fodder plant will remain important, mainly in conjunction with its control as a weed. Literature 111 Auld, B.A., 1994. Potential of mycoherbicides in Malaysia. In: Caunter, I.G. & Sastroutomo, S.S. (Editors):Appropriate weed control in Southeast Asia. Proceedings of an FAO-CAB International workshop, Kuala Lumpur, Malaysia, 17-18 May 1994. pp. 42-47. 121 Gopal, B., 1987. Water hyacinth. Aquatic plant studies 1. Elsevier, Amsterdam, the Netherlands. 471 pp. 131 Low, K.S., Lee, C K . & Tan, K.K., 1995. Biosorption of basic dyes by water hyacinth roots. Bioresource-Technology 52: 79-83. I4l Penfound, W.T. & Earle, T.T., 1948. The biology of the water hyacinth. Ecological Monographs 18: 447-472. I5l Pieterse, A.H., 1978. The water hyacinth (Eichhornia crassipes) - a review. Abstracts on Tropical Agriculture 4(2): 9-42. 161Pieterse, A.H. & Murphy, K.J. (Editors), 1990. Aquatic weeds, the ecology and management of nuisance aquatic vegetation. Oxford University Press, Oxford, United Kingdom. 593 pp. l7l Quinones, N.C. & Bravo, M.V., 1993. Rediscovering the uses of water hyacinth. Canopy International 18(5): 1, 3-4. I8l van Thielen, R., Ajuonu, O., Schade, V., Neuen-

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schwander, P., Adité, A. & Lomer, C.J., 1994. Importation, releases, and establishment of Neochetina spp. (Col.: Curculionidae) for the biological control of water hyacinth (Eichhornia crassipes Lil.: Pontederiaceae) in Benin, West Africa. Entomophaga 39: 179-188. I9l Yeoh, B.G. & Odegaard, H., 1993. Use of water hyacinth (Eichhornia crassipes) in upgrading small agroindustrial wastewater treatment plants. Water Science and Technology 28:207-213. A.H. Pieterse

Erythrina fusca Loureiro Fl. Cochinch.: 427 (1790). LEGUMINOSAE - PAPILIONOIDEAE

In =42 Synonyms Erythrina glauca Willd. (1801), E. ovalifolia Roxb. (1832), E. atrosanguinea Ridley (1911). Vernacular n a m e s Purple coral-tree, coral bean, swamp immortelle (En). Bucayo (Am). Bois immortelle, immortelle blanc (Fr). Indonesia: cangkring (Javanese, Sundanese), rase, kane (southern Sulawesi). Malaysia: dedap, dadap. Papua New Guinea: maor (Lamekot), vatamida (Ugana). Philippines: anii (Tagalog), korung-korung (Bisaya). Cambodia: roluöhs phâ-'aông. Laos: th'o:ng hla:ng. Thailand: thonglang nam, thonglong (central). Vietnam: v[oo]ng d[oo]ng (Ho Chi Minh City), v[oo]ng gai (Quang Nam), c[aa]y son dong (Annamese). Origin and geographic distribution E. fusca is the most widespread species in the genus Erythrina L. occurring wild in both the Old and New World tropics. In Asia and Oceania it occurs along coasts and rivers from India to the Philippines, New Guinea and Polynesia; in Africa in Madagascar, the Mascarene Islands, the Comoro Islands and Pemba Island, but not in continental Africa; in Central and South America in the West Indies, throughout the Amazon basin, and along the coast of Brazil, Colombia, up to Honduras and Guatemala. It is now planted throughout the humid tropics. U s e s E. fusca is widely planted as a shade tree in cocoa and coffee plantations in Central and South America and, less frequently, in South-East Asia. In Sumatra and Central America, pepper and vanilla vines are commonly planted with E. fusca as live stakes. In Costa Rica, E. fusca is occasionally used in live fences, though much less commonly than E. berteroana Urban and other

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Erythrina spp. In Central America it is used as a source of fodder. The young leaves are eaten as a vegetable in Java and Bali, the flowers in Guatemala. In Indonesia the bark is used for poulticing fresh wounds, and bark or root decoctions against beri-beri. Like many Erythrina spp. it is often planted for ornamental purposes. Properties The edible portion ofthe leaves contains per 100 g dry matter: 20-22 g crude protein; in vitro digestibility ranges from 30-55%. The mineral content ofthe leaves per 100 g dry matter is: N 3.2 g, P 0.15 g, K 1.0 g, Ca 1.3 g, Mg 0.5 g. As in other Erythrina spp., the seed contains very small amounts of free amino acids and large amounts of alkaloids. In E. fusca, only the amino acid histidine occurs in fairly large amounts (0.6-1.0%), which is characteristic of the species. The only common Erythrina alkaloids found in E. fusca are erysotrine, erythraline, erysodine, erysovine and erysopine. Ant-repellent compounds in the nectar have been reported. The weight of 1000 seeds is 200-700 g. The wood is soft with a moderately coarse texture and an unattractive, straight grain. Growth rings are absent, axial and radial parenchyma fairly abundant. The colour of the wood is white to yellow, without differentiation between the heartwood and the sapwood. The average air-dry density ranges from 250-300 kg/m3. Description A medium to large, spreading tree, 10-15(-26) m tall, crown rounded; trunk short, spiny (spines 1-2 cm long), much branched, sometimes buttressed to 2 m; bark brownish-grey or olive-brown, flaky. Branches spreading, spiny; branchlets stout, spineless or aculeate. Leaves alternate, trifoliolate; stipules and stipels orbicular, caducous; petiole up to 25 cm long, sometimes sparsely prickly; rachis up to 5 cm long, petiolule up to 1.5 cm; leaflets ovate to elliptical, 2.5-20 cm x 1.5-15 cm, subcoriaceous, rounded or subacute at both ends, pale green above, glaucous or greyish-green beneath, glabrous to velvety hairy. Inflorescence racemose, terminal, appearing when leaves are present, with pale brick-red or salmon (seldom white) flowers in fascicles scattered along the rachis, covered with deciduous, ferruginous hairs, mostly unarmed; peduncle up to 13cm long; rachis 8-30 cm long; pedicel up to 2 cm long; bracts and bracteoles ovate, up to 2.5 mm x 2 mm, deciduous; calyx asymmetrical, broadly campanulate, about 1.5 cm long, lacerate or subentire but with a 0.5-1.5 mm long spur on the keel side, pubescent; standard rounded-rhombic, 4-7 cm x

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Erythrina fusca Loureiro - 1, habit; 2, flowering branch; 3, flower; 4, flower (petals removed); 5, pod. 3.5-6 cm,reflexed, orange or scarlet, broadly folded down the middle, claw 9mm long; keel slightly longer than the wings, both about half the length ofthe standard; stamens 10,4-6 cmlong, 1free, 9 united in lower half into staminal tube; pistil 4-6 cm long, ovary densely pubescent. Fruit a woody, linear, compressed pod,14-33cmx 14-18 mm, dehiscent, slightly constricted between the 3-15 seeds, stipe stout, 1.5 cmlong, beak 2cmlong, velvety ferruginously hairy when young, later glabrescent. Seed oblong-ellipsoid, 12-18 mm x 5-8 mm,dark brown or black. Growth and development Young plants nodulate well under natural conditions. Trees flower when in leaf, and flowers are frequently visited and pollinated by birds. Fruits mature in approximately twomonths. Other botanical information Trees nearlydevoid of spines exist and have also been bred. Hybridization is frequent where several Erythrina species co-occur. Ecology E. fusca is found from sea level up to

2000 m altitude, within a wide range of rainfall patterns, from 1200mm to over 3000 mm annually, with or without a seasonal distribution. Average daily temperatures range from 16-24°C at the higher elevations to over 26°C in the lowlands. It seems to prefer littoral locations with badly drained soils like swamps and stream banks and upland riverine marshes. In low-lying freshwater swamps E. fusca attains huge dimensions and sometimes develops almost pure stands. In anexperiment in Cauca, Colombia, on an acid soil of pH 4.3 and an aluminium saturation of 80%, it showed better growth than Samanea saman (Jacq.) Merrill and Delonix regia (Bojer ex Hook.) Rafinesque, which are considered tolerant of such conditions. Seeds ofE. fusca float in water and are dispersed by ocean currents. They have been found on the beaches of cays ofthe Great Barrier Reef of Australia. E. fusca and E. variegata L. were among the first species to colonize Krakatau Island (Indonesia), only a few years after the cataclysmic eruption in 1883. Propagation and planting When used as a shade or nurse tree, E. fusca is propagated by large cuttings, about 2 m long and 6-10 cm in diameter. Rooting success is excellent, provided soil moisture is close to field capacity. Cuttings start sprouting in 2-4 weeks. E. fusca can also be propagated easily by seed. Fresh seed has a germination rate of 80-95%. In Costa Rica, trees supporting black pepper vines are planted at a density of 1600 trees/ha. Husbandry Established trees withstand regular pruning very well. They start sprouting rapidly and develop strong shoots. In Mexico, when shading cocoa, E. fusca is managed under a moderate regime of pruning. Trees are partially pollarded once every 1-2 years, leaving a few branches per tree to regulate light influx to the crop. In the per-humid, tropical lowlands ofCosta Rica, on alluvial soil, a 6-month pollarding cycle is used for trees supporting black pepper vines (Piper nigrum L.). Annual dry matter production from prunings of 1600trees/ha (without natural litter fall) is 3.4 t/ha, corresponding to an N application of 124 kg/ha. In Bahia, Brazil, it was observed that cocoa trees planted near E. fusca produced more pods than those growing further away from the shade trees. Increased litter fall in plantations with E. fusca added to the available amounts ofN and P in the system, while daily évapotranspiration was reduced from 901/tree in unshaded cocoa trees to40

ERYTHRINA

l/tree in shaded trees on sunny days. On overcast days, the reduction was about 40%, from 45 1/tree to 26 1/tree. Diseases and pests Under conditions of high relative humidity the bark of E. fusca may be attacked by fungi such as Calostibe striipora. In pepper plantations in Sumatra, stakes of Erythrina spp. are frequently attacked by stem-borers. The damaged stakes may fall over and the pepper will not produce fruits properly. Two species of borer insects have been found, a stemborer (Batocera sp.) and a ring-borer (family Lecanidae). In alley cropping,Erythrina spp. may act as a host to diseases and pests of the associated crops. In Peru, the use of Erythrina spp. in alley cropping has already been discouraged due to an increase of shoot and fruit borers. In India, an increased number of root-knot nematodes (Meloidogyne incognita) has been observed in cardamom plantations with E. fusca. Genetic resources A collection of Erythrina spp. of over 70 entries has been established at the Waimea Arboretum in Haleiwa, Hawaii. The Tropical Agricultural Center for Research and Training (CATIE) in Turrialba, Costa Rica, maintains a collection of 28 species of Erythrina. Both collections include E. fusca. Breeding A breeding and selection programme is in progress at CATIE. Cultivars are being selected for absence of spines, branching habit, biomass characteristics for livestock fodder and capacity to retain their leaves during the dry period. Prospects E. fusca may be of special interest in the development of agroforestry systems for the per-humid tropics, due to its adaptability, ease of propagation from cuttings, ability to withstand regular pruning, and the rapid sprouting and development of shoots. However, diseases and pests should be monitored closely, as they may affect both E. fusca and the associated crops. The feasibility of using it as a nurse tree for other tree species in reforestation projects in the tropics is an alternative to be explored. Literature 111Baretta-Kuipers, T., 1982. Wood structure of the genus Erythrina. Allertonia 3(1): 53-69. 121 de Oliveira Leite, J. &Valle, R.R., 1990. Nutrient cycling in the cacao ecosystem: rain and throughfall as nutrient sources for the soil and cacao tree. Agriculture, Ecosystems and the Environment 32: 143-154. 131 Gillett, J.B., Polhill, R.M. & Verdcourt, B., 1971. Erythrina. In: Milne-Redhead, E. &Polhill, R.M. (Editors): Flora of tropical East Africa. Leguminosae 4, Papilionoideae 2.

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Crown Agents for Oversea Governments and Administrations, London, United Kingdom, p. 547. 141Krukoff, B.A., 1939. The American species of Erythrina. Brittonia 3: 224-227. I5l Muschler, R.G., Nair, P.K.R. & Menendez, L., 1993. Crown development and biomass production of pollarded Erythrina berteroana, E. fusca and Gliricidia sepium in the humid tropical lowlands of Costa Rica. Agroforestry Systems 24: 123-143. 161 Neill, D.A., 1988. Experimental studies on species relationships in Erythrina (Leguminosae: Papilionoideae). Annals of the Missouri Botanical Garden 75: 886-969. 171 Russo, R.O., 1990. Erythrina: a versatile nitrogen-fixing woody legume genus for agroforestry systems in the tropics. Journal of Sustainable Agriculture 1(2):89-109. R.O. Russo &N.T. Baguinon

Erythrina poeppigiana (Walpers) O.F. Cook Bull. U.S. Dept. Agric. Div. Bot. 25:57 (1901). LEGUMINOSAE - PAPILIONOIDEAE

2ra=42 Synonyms Erythrina micropteryx Poeppig ex Walpers (1850), Micropteryx poeppigiana Walpers (1850). Vernacular n a m e s Mountain immortelle, coral tree (En). Bois immortelle (Fr). Poró gigante, bucayo gigante (Sp). Indonesia: dadap. Similar vernacular names often refer to other Erythrina spp. as well. Origin and geographic distribution E. poeppigiana occurs naturally in South America, from Venezuela and Panama in the north, throughout the Andean foothills of Colombia, Ecuador, Peru and Bolivia to the western parts of the Amazon basin in the south. It is now extensively planted and naturalized in Central America and the Caribbean. It has been introduced into the humid tropics of the Old World, including South-East Asia. Uses E. poeppigiana is one of the most commonly planted shade trees in cocoa, coffee and pepper plantations in Central America, often planted in combination with the agroforestry tree Cordia alliodora (Ruiz & Pavon) Oken. It is valued for its high production of green manure and mulch, the ease with which shade can be adjusted to the requirements of the main crop and its ability to tolerate regular coppicing for many years. It is used occasionally as a shade tree in Indonesia. It is used less frequently in live fences and as a

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shade and forage tree in pastures, e.g. in association with Cynodon plectostachyus (K. Schum.) Pilger, C. nlemfuensis Vanderyst and Pennisetum purpureum Schumach. Leaves are cut for fodder for cattle and goats. Pigs are reported to suffer from hair loss when fed with E. poeppigiana loppings. Seeds and leaves are reportedly used medicinally in the countries of origin. Seeds also yield a fish poison. Like several other Erythrina spp., trees are often grown as ornamentals for their bright orange-red flowers. In Colombia, the flowers are eaten in salads and soups. The wood is of very limited value, even making only poor quality firewood. It is used occasionally for poles and posts, sometimes for vegetable crates, pulp or particle board. Lopped branches have no value as wood. Properties The edible biomass contains per 100 g dry matter (22-)27-34 g crude protein with an in vitro digestibility of 50-80%. Mineral content of prunings per 100 g dry matter is: leaves: N 3.1 g, P 0.24 g, K 1.3 g, Ca 1.6 g, Mg 0.5 g; branches: N 1.2 g, P 0.15 g, K 1.3 g, Ca 1.25 g, Mg 0.4 g. Fallen leaves contain per 100 g dry matter: N 2.2-2.6 g, P 0.14-0.15 g, K 0.5-0.6 g, Ca 1.9-2.2 g, Mg 0.5-0.7 g. Branches in natural litter contain per 100 g dry matter: N 1.3 g, P 0.1 g, K 0.7 g, Ca 2.0 g, Mg 0.7 g. Mineral content is influenced by the pruning regime. Frequent pruning increases the proportion ofleaves and the N content ofthe loppings. Like other Erythrina spp., E. poeppigiana contains curare-like alkaloids with a muscle relaxant or paralysing action and uncommon, non-protein amino acids assumed to have insecticidal properties. The alkaloids have been subject of extensive pharmaceutical tests. Species can be identified by the alkaloid profile of the seeds. E. poeppigiana contains erysotrine and its derivatives erythratidine and erythroidine. These alkaloids are not poisonous to ruminants in the quantities present in normal rations. The wood is characterized by abundant thinwalled, axial and radial parenchyma. It is soft, light in weight (specific gravity 250 kg/m 3 ), whitish to yellowish. Heartwood can not be distinguished from sapwood. Large vessels, the prominent rays and parenchyma bands are easily visible using a hand lens. The seed weight of 100 seeds is 15-30 g. Description A sometimes multi-stemmed, deciduous, often spiny tree with spreading crown, up to 25 m tall and 1.2 m in trunk diameter; when cultivated it is generally kept small, by cutting the

Erythrina poeppigiana (Walpers) O.F. Cook - 1, leaf;2, inflorescence; 3, infructescence. stem to 2-2.5 m. Bark greenish-brown to greybrown, nearly smooth or slightly furrowed, warty or spiny. Twigs stout, spiny, light green and puberulous when young, becoming greenish-grey, with raised leaf scars. Leaves alternate, trifoliolate, thin-chartaceous, often scabrous beneath, glabrescent; petiole 10-40 cm long; rachis up to 30 cm long, with cup-like stipellar, nectar-producing glands at the base of lateral leaflets; petiolules up to 1.5 cm long; leaflets ovate to rhombic, terminal one 8-30 cm x 5-30 cm. Inflorescence an axillary raceme, borne horizontally at distal end of shoots, densely and finely tomentellous; peduncle 4-8 cm long; rachis 7-40 cm long; pedicel 0.5-1.2 cm long, very finely tomentellous or puberulent; bracts and bracteoles ovate, up to 1.3 mm x 0.8 mm; calyx campanulate, 5-10 mm long and wide, orange to reddish at the top, entire but with 2 mm long spur on keel side; standard elliptical, 3-5 cm x 1.5-2.5 cm, bright orange, erecto-patent or slightly recurved, claw 1.5 mm long; wings spatulate to obovate, 7-14 mm x 3-6 mm; keel falcate, 3-5 cm x 0.5-1 cm; stamens 10, 1free, 9 tubular connate at

ERYTHRINA

base, 3-5 cm long, separate for 0.5-1cm;pistil up to 5cmlong, with linear, puberulent ovary and filiform style. Pod 13-25cmx 1-1.5 cm, chartaceous, not constricted between seeds, stipe 3-4 cm long, beak 4-8mm.Seed oblongoid to ellipsoid to slightly reniform, 10-17 mm x 5-7 mm, glossy-brown, without markings. Growth and development Mature seed germinates readily. The germination rate is 60-90%, decreasing with storage time. Under favourable conditions, seedlings attain 60-85 cmheight anda basal diameter of 2-3 cm in 4 months. In 6 months, trees can attain a height of4-5 m anddevelop a crown of 3-4 m diameter with up to 15 branches. The growth of the tree follows the architectural model of Attim. The main and lateral shoots display indeterminate growth. Most mature trees shed their leaves early in the dry season. Leaf abscission is generally followed by flowering. Flowers open acropetally onnewly formed lateral inflorescences at the distal ends of shoots. Fruits develop on leafless trees, maturing in about 2 months, and new shoots emerge during or after fruit maturation. However, this development may be asynchronous within the crown of large trees; on upper branches leaves may abscise and flowers may develop, while lower branches retain their leaves. Trees in some areas shed their leaves again at the end of the wet season, but this leaf fall is not followed by a flush of flowers. Where a dry season is absent, trees are never bare and flower when in leaf. Near the equator trees may flower twice a year. The processes of leaf and flower development seem tobe controlled by internal moisture conditions. The increased availability ofmoisture immediately after leaf fall has been suggested as a stimulus for flowering. E. poeppigiana is capable ofatmospheric nitrogen fixation by nodulation with Bradyrhizobium. Successful inoculation has been obtained with strain CIAT 71. Nodulation starts early and plantlets may contain up to 80 nodules 3 months after sowing. Nodules are 1.5-10 mm in diameter, spherical and clustered onthe central root system at the point ofemergence oflateral roots. Theyoccur only in the top 10-12cmofthe soil, mainly in the area under the crown ofthe tree. The biomass of the root nodules varies from 80-250 mg dry matter per dm 3 soil and is largest close to the stem. Pollarding affects nitrogen fixation of the trees. Some ofthe root nodules and part ofthe root system disintegrate after the tree has been pruned.

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New roots and nodules form when the development ofnew foliage iswell underway. Other botanical information The species of Erythrina L. can, as far as is known, all be intercrossed toproduce fertile hybrids. E. poeppigiana is pollinated by many non-specialized perching or sparrow-like birds. The amount ofnectar intheflowers mayreach 50ugper flower and is so great that insects would visit too few flowers tobeeffective distributors ofpollen. Ecology In cultivation, E. poeppigiana can adapt to a wide range of conditions. It is found from (0-)500-1500(-2000) m above sea level in the tropics with annual rainfall ranging from 1200-3000 mm,with a period ofup to6 months of reduced rainfall. Average annual temperatures may vary from 18-28°C. Above 2000 m altitude, trees become blanketed with epiphytes and stunted, butmaysurvive upto2400 m. It will grow on a wide range of soils, from heavy clay to medium loam, ranging from acid to alkaline, butvery acid soils arenot tolerated. Trees are resistant to fire, including controlled burning. Propagation E. poeppigiana is sometimes propagated by seed, suckers or air layering, but farmers usually propagate it by large stem cuttings, 2-2.5m long and8-12cmin diameter, readily obtainable from 2-year-old branches. Sprouting starts within a month after planting, and in 4-6 months the new trees start shading coffee seedlings. Rooting success varies from 70-90%. Methods of in vitro propagation are being developed. Husbandry Established shade trees in coffee or cocoa plantations are normally completely or partially pollarded once or twice a year. Timing and intensity of pruning can be adjusted to prevailing conditions and the requirements of the associated crop. In coffee plantations, trees are usually pruned prior to flowering and again before ripening of the crop, or at the beginning of the long and the short rainy seasons. Additional pruning is sometimes carried out during prolonged periods of extremely cloudy weather. To maintain a low shade canopy the calloused trunk tip is sawn off every 5-6 years. Trees tolerate pollarding well and canbe treated this wayfor many years. E. poeppigiana produces large quantities of prunings and litter. Planted at a density of 280 trees per ha in a coffee plantation under experimental conditions in Costa Rica, pollarding once a year produced 18.5 t drymatter perha ofprunings and

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4.3 t dry matter per ha of natural litter. Of the primings 3.2 t were leaves, 15.2 t were branches. When pollarded twice a year, annual dry matter production fell to 11.8 t/ha of prunings and 1.9 t/ha of natural litter. Three prunings per year resulted in an annual dry matter production of 7.9 t/ha of prunings, consisting of 4.3 t of leaves and 3.5 t of branches. No natural litter fall occurred under the latter pruning system, as the life span of leaves exceeds 4 months. Prolonging the pruning interval thus results in a greatly increased production ofbranch wood and a gradual decrease in the production of leaves. Leaf production of the associated coffee crop is also larger than in coffee grown without shade. In cocoa plantations with a similar density of E. poeppigiana comparable amounts ofprunings and litter are found. The amounts ofnutrients recycled in the prunings are considerable and mostly match fertilizer recommendations for intensively managed coffee. In the pollarding experiment mentioned, annual pollarding resulted in contributions per ha of 330 kg N, 32 kg P, 156 kg K, 319 kg Ca, 86 kg Mg. When pollarding three times per year annual contributions per ha were: 173 kg N, 14kg P, 119 kg K, 94 kg Ca, 27 kg Mg. Amounts for pollarding twice a year were intermediate. Although considerable amounts of nutrients are recycled, large quantities are immobilized in the stems as well. The total amount of available P in the soil and the litter layer may actually diminish under E. poeppigiana. However, when trees are pollarded 2 or 3 times per year, most ofthe stored nutrients are recycled. It was found that most of the nitrogen recycled was taken up from the soil. N balance studies indicate that up to 60 kg atmospheric N per ha may be assimilated annually, even when the crop receives mineral N fertilizer. This is comparable to several other woody legumes, but less than the quantities reached by Leucaena leucocephala (Lamk) de Wit. There is little information on the durability of the mulch layer. Studies indicate that 50% of the organic matter decomposes within 1month and 75% in 6 months. The decomposition of organic material may cause the pH to decline in certain soils, which may result in increased leaching of K, Ca and Mg. The high production of organic matter in prunings results in an increase in soil organic matter. In a ten-year experiment with E. poeppigiana and cocoa, the soil organic matter increased from a relatively high initial amount of 200 t/ha to 240 t/ha. This contributes to very low levels of leaching of

minerals, comparable to those in natural or planted forests. Neither the intensity nor the effects of the shade of E. poeppigiana have ever been measured systematically and directly. In long-term trials with maize (Zea mays L.), grown in the rainy season, followed by a dry season crop of common bean (Phaseolus vulgaris L.), both crops showed considerable yield increases in response to an annual mulch of 20 t/ha ofE. poeppigiana prunings. The N utilization by the crops was somewhat less efficient than with mineral N fertilizer. The cut-and-carry mulch system was superior to an alley-cropping system with the same crops. The yield advantages were smaller in the alley-cropping system. An economic analysis of the systems showed the cut-and-carry system to be more profitable in spite of the high labour requirements. Cassava (Manihot esculenta Crantz) yields could not be maintained, either in the mulch system or in the alley-cropping system. E. poeppigiana has been tested as shade and forage tree with a number of grasses, e.g. king grass (a hybrid of Pennisetum purpureum and P. glaucum (L.) R. Br.) and Cynodon nlemfuensis. Yields of the grasses were not reduced and sometimes even increased under E. poeppigiana. The protein content increased. However, after a few years, yields started to decline because of the large loss of nutrients caused by removing cut grass and E. poeppigiana loppings. Leaves of E. poeppigiana are readily accepted by livestock and may increase the amount of feed ingested and milk produced. Diseases and pests E. poeppigiana is not seriously affected by diseases or pests. It is termite resistant even when regularly pollarded. Genetic resources The Nitrogen Fixing Tree project maintains a collection of 28 species and about 75 accessions of species commonly used in Costa Rica at the Centro Agronómico Tropical de Investigation y Ensenanza (CATIE), Turrialba. Another large collection of species of Erythrina is maintained in the Waimea Arboretum, Haleiwa, Hawaii. Breeding At CATIE, Turrialba, selections have been made on the basis of desirable characteristics such as absence ofspines, branching habit, capacity to retain leaves during the dry season and value as forage crop. Selection trials are still in progress. As the selections used in Central America seem to be derived from a very limited number ofintroductions, there is ample scope for including genetic materials from the regions of origin.

ERYTHRINA

Prospects Its fast growth, ability to produce large amounts of biomass and to fix atmospheric nitrogen, ease of propagation from cuttings, excellent response to pruning and high content of crude protein mean that E. poeppigiana has excellent potential for various agroforestry practices not only in Central America but throughout the humid tropics. It plays a central role in agroforestry and alley-cropping research work at CATIE, Turrialba, Costa Rica. Besides its role as shade tree, it fits in well in alley cropping with annual crops and pasture grasses. Its productivity and the good digestibility of its protein make it a promising forage crop. The low value of the wood is compensated by other qualities. Literature 111Beer, J., 1988. Litter production and nutrient cycling in coffee (Coffea arabica) or cacao (Theobroma cacao) plantations with shade trees. Agroforestry Systems 7: 103-114. 2 Bordiert, R., 1980. Phenology and ecophysiology of tropical trees: Erythrina poeppigiana O.F. Cook. Ecology 61: 1065-1074. 131 Fassbender, H.W., Beer, J., Heuveldop, J., Imbach, A., Enriquez, G. & Bonneman, A., 1991. Ten year balances of organic matter and nutrients in agroforestry systems at CATIE, Costa Rica. Forest Ecology and Management 45: 173-183. 141 Krukoff, B.A., 1939. The American species of Erythrina. Brittonia 3: 235-238. 151 Pezo, D., Kass, M., Benavides, J., Romero, F. & Chaves, C , 1990. Potential of legume tree fodders as animal feed in Central America. In: Devendra, C. (Editor): Shrubs and tree fodders for farm animals. Proceedings of a workshop in Denpasar, Indonesia, 24-29 July, 1989. International Development Research Centre of Canada (IDRC), Ottawa, Canada, pp. 163-175. 161 Ramirez, C , Sanchez, G., Kass, D., Viquez, E., Sanchez, N., Vasquez, N. & Ramirez, G., 1989. Advances in Erythrina research at CATIE. In: Werner, D. & Müller, P. (Editors): Fast growing trees and nitrogen fixing trees. Fisher Verlag, Stuttgart, Germany, pp. 96-105. |7| Russo, R.O., 1990. Erythrina: a versatile genus for agroforestry systems in the tropics. Journal of Sustainable Agriculture 1: 89-109. 181 Russo, R.O. & Budowski, G., 1986. Effect of pollarding frequency on biomass of Erythrina poeppigiana as a coffee shade tree. Agroforestry Systems 4: 145-162. L.P.A. Oyen

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E r y t h r i n a s u b u m b r a n s (Hassk.) M e r r i l l Philip. J. Sei. Bot. 5: 113 (1910). LEGUMINOSAE - PAPILIONOIDEAE

2« = 42 Synonyms Erythrina lithosperma Miquel (1855), Hypaphorus subumbrans Hassk. (1858), Erythrina hypaphorus Boerl. (1899). Vernacular n a m e s December tree (En). Indonesia: dadap duri (general), dadap rangrang (Sundanese), dadap ri (Javanese) (armed forms); dadap minyak (general), dadap lesang (Sundanese), dadap lenga (Javanese) (thornless forms). Malaysia: dedap batik, cengkering. Papua New Guinea: dadap. Philippines: dap-dap (Tagalog), rarang (Bikol), anii (Bisaya). Burma (Myanmar): ye-katit. Laos: th'o:ng hla:ng. Thailand: thonglang-pa (northern), thong-lang (central). Origin and geographic distribution E. subumbrans occurs naturally from India and Sri Lanka, throughout South-East Asia (except New Guinea) to Fiji and Samoa. Now it is distributed throughout the tropics. Uses E. subumbrans was one of the most widely planted shade trees for coffee and other crops in Indonesia, until large numbers of trees were destroyed by a root disease in the late 19th Century. It is still planted on a smaller scale in Indonesia for shade in cocoa, coffee and tea plantations, and as live support for betel (Piper betle L.), pepper (Piper nigrum L.) and vanilla (Vanilla planifolia H.C. Andrews) vines. In Malaysia, it is used as a shade tree for coffee and tea; in Western Samoa, as a shade tree for cocoa and taro (Colocasia esculenta (L.) Schott) and as a live support for yams (Dioscorea spp.). In Burma (Myanmar) and India, it is often grown to support betel and pepper vines. In Sri Lanka, it is the most common shade tree for tea and cocoa. Very young leaves are steamed and eaten in salads in Java. The leaves are a good and palatable fodder but if eaten by rabbits it can cause sterility and death. In Western Samoa, an addition of 5% leucaena meal and 5% dried and ground dadap meal to the starter diets of chicken improved their gains in weight. Bark and leaves are used medicinally, sometimes mixed with parts of other plants. A decoction of the bark is taken to treat spleen afflictions in the Philippines. In Indonesia pounded young leaves are used as a poultice for women soon after giving birth and against headache;juice of leaves is used as an eye-wash and a decoction of the leaves is

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given for coughs. The wood is utilized in canoe and raft building. In Papua New Guinea, trees are planted near villages for their showy red flowers, while in certain districts (e.g. Morobe) they are used in ritual ceremonies. Properties Loppings ofE. subumbrans provide a quickly decomposing green manure, containing per 100 g dry matter: N 1.5-3 g, P 0.2-0.35 g, K 1-2 g. Flowers contain large quantities of nectar and are a major source of food for birds during the dry season in East Java. Seeds contain the curarelike alkaloids erysoline, erysopine and erythratine. The wood ofE. subumbrans is soft and light, with an air-dry density ranging from 335-385 kg/m 3 . The sapwood is not differentiated from the heartwood, which is light straw-coloured. Texture is coarse and uneven due to the presence of broad rays and abundant confluent parenchyma conspicuous to the naked eye. Grain is straight, shallowly interlocked or spiral. Growth rings are absent. Vessels are about 310 ^m in diameter, few, solitary, in radial groups of2to 3. Description A deciduous, medium-sized tree, 5-25 m tall, trunk reaching 60 cm in diameter; crown spreading; bark whitish; trunk and branches armed with stout prickles, in cultivation mostly unarmed. Leaves alternate, trifoliolate; stipules orbicular, small, caducous; rachis 10-21 cm long, inclusive of the petiole of 8-16 cm which is thickened at the base; petiolule up to 7mm long; stipels 2, below the lateral leaflets, stipitate, cup-like, glandular, 2 mm long; leaflets ovate-triangularrhomboid, terminal one largest and 8-16 cm x 6-14 cm, base rounded or cordate, apex acuminate, glabrous. Inflorescence racemose, in the upper leaf axils, 5-23 cm long, brownish-tomentose; flowers many, arranged in groups of 3; peduncle terete, robust, 3-15 cm long, pubescent; pedicel 2-3 mm long, in fruit up to 6 mm; calyx campanulate, 1-1.5 cm long, splitting open up to halfway down, tomentose, yellow-green; petals 5, red; standard broadly elliptical, shortly clawed, 2.5-4 cm x 2-3 cm, scarlet, at base inside with numerous white stripes; wings as long as the keel or slightly longer, about 1.5 cm long, pale red with a blackish upper margin; stamens 10, 3-3.5 cm long, monadelphous but vexillary stamen slightly shorter than other ones and only connate for the lower 0.5-1 cm, pinkish red; pistil with hairy ovary. Pod flat, curved, 10-15 cm long, on a slender stalk 3-4.5 cm long, lower part seedless and 2-2.5 cm wide, upper part thicker, 1-1.5 cm wide and 1-5-

Erythrina subumbrans (Hassk.) Merrill - 1, part of prickly branch; 2, flowering branch; 3, inflorescence; 4, flower; 5, flower (petals removed); 6, pod; 7, seed. seeded, septate between the seeds, dehiscent. Seed ellipsoid, 7-18 mm x 5-11 mm, smooth, dull black. Growth and development E. subumbrans forms large numbers of effective root nodules. In Singapore it flowers from October to December during the height of the wet season. In Java, flowering and fruiting occur almost throughout the year, with peaks in February-March and October-November. Thornless forms generally produce fewer flowers and fruits than the armed, wild ones. As in other Erythrina spp., the red, odourless, nectar-rich flowers are so constructed that cross-pollination is universal. Pollination is by birds which feed on the abundant nectar. Some ofthe leaves are shed during the dry season. However, in Java, trees are never completely leafless. Pruning before the start of the dry season can prevent leaves being shed during the dry season. Cultivated thornless forms may reach an age of 40-50 years but often die earlier because of dis-

ERYTHRINA

eases and pests. Other botanical information Most Erythrina spp. are ecologically separated, even when occurring in the same geographical region. Hybrids, however, occur frequently in cultivation, as there appear to be no barriers to interspecific hybridization. An unarmed hybrid between E. subumbrans and E. variegata L., named 'dadap Solo', probably originated near Surakarta in Java, and is widely planted. It is shorter than other unarmed forms of E. subumbrans, has a denser crown and rarely produces viable seed. The necklace-shaped pods of E. subumbrans are highly characteristic and can be used to identify the species. Ecology E. subumbrans occurs at low and medium altitudes, from (0-)300-1500 m, in moist valleys, near streams, in open locations and secondary forest. It requires a high annual rainfall with a maximum of 4 months with less than 100 mm rainfall, and a mean annual temperature above 22°C. It is reported, however, to occur gregariously on the Ijen plateau in East Java, in open grassland in stony or sandy, occasionally dry places; elsewhere it is widely dispersed. The trees are fairly tolerant of wind, unless branches have been damaged by borers. Seeds are dispersed by water and occasionally by birds. Propagation and planting E. subumbrans grows easily from large cuttings, even if they are 25 cm in diameter. It can be propagated by seed, but seedlings of thornless trees are generally armed. The spacings employed depend on the spacing of the main crop, pruning regime, and growth rate of the trees. In Western Samoa, a spacing of 1.5 m x 1.5 m is used in cocoa, 2 m x 2 m when planted as a shade for taro. Husbandry Pruning and pollarding are very well tolerated. In tea plantations in Sri Lanka it is customary to pollard twice a year. In coffee and tea plantations in Java, pruning is generally done once a year. The frequency of lopping depends on the requirements ofthe main crop, the labour supply and the growth rate of the trees and can be up to 4 times per year. However, mortality may occur if pruning is followed by a prolonged dry spell. Where E. subumbrans is pruned, it is sometimes used as a medium level shade tree, interplanted with taller shade trees like Paraserianthes falcataria (L.) Nielsen or Grevillea robusta Cunn. ex R. Br. Elsewhere, E. subumbrans is not pruned and is used for high shade, interplanted with Leucaena leucocephala (Lamk) de Wit providing low shade.

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In Western Samoa, yam vines planted in a circle around an E. subumbrans tree are allowed to cover the canopy and suppress its growth. Diseases and pests At the end ofthe 19th Century in Java, E. subumbrans was heavily attacked by a root disease, which locally destroyed all trees and prevented its further planting. Little has been published about this disease, its cause and importance today. The fungus Septobasidium bogoriense often grows on the bark. It does not cause direct damage, but keeps the bark moist, creating favourable conditions for pathogenic fungi like Corticium salmonicolor, Fomes spp., and Ustulina zonata. Several boring insects attack the wood and bark of branches, often causing them to break and making them susceptible to rot. The leaves of E. subumbrans are damaged by many insects and defoliation is common. Normally, the trees recover rapidly. Prospects Where E. subumbrans is not too seriously affected by diseases and pests, it is one of the best shade and live support trees for a wide range of crops. It is fast growing, fixes atmospheric nitrogen, provides easily decomposing litter and its shade can be well adjusted to the requirements of the main crop. A programme for the selection of disease-tolerant cultivars would be well justified. Its neat appearance makes it a good ornamental and amenity tree. Literature 111 Brennan, E.B., 1992. A new grafting technique for Erythrina, Leucaena, and possibly other nitrogen fixing tree species. Nitrogen Fixing Tree Research Reports 10: 85-88. 12 Chee, T.Y. & Ridwan, S., 1984. Fast growing species of trees suitable for urban roadside and shade planting. Malaysian Forester 47(4): 2 6 3 269. 131 Filius, A.M., 1982. Economic aspects of agroforestry. Agroforestry Systems 1: 29-39. 141 Kay, D.E., 1970. The production and marketing of pepper. Tropical Science 12: 201-206. 151 Martin, F.W., 1984. Edible leaves from nitrogen fixing trees. Nitrogen Fixing Tree Research Reports 2: 57-58. 161 Nguyen Van Thuân, 1979. Leguminosae-Papilionoideae, Phaseoleae. In: Aubréville, A. & Leroy, J.F. (Editors): Flore du Cambodge, du Laos et du Vietnam. Vol. 17. Muséum National d'Histoire Naturelle, Laboratoire de Phanérogamie, Paris, France, pp. 25, 27. 171 Raharjo, Y.C. & Peter, R.C., 1985. Palatability of tropical tree legume forage to rabbits. Nitrogen Fixing Tree Research Reports 3:31-32. 181 Rogers, S., Iosefa, T. & Rosecrance, R., 1993. Development of an Erythrina-based agroforestry system for taro cropping in

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Western Samoa. In: Westley, S.B. & Powell, M.H. (Editors): Erythrina in the New and Old Worlds. Nitrogen Fixing Tree Research Reports, Special Issue. Nitrogen Fixing Tree Association, Paia, Hawaii, United States, pp. 200-204. 191 Seibert, B., 1988. Living poles for pepper (Piper nigrum L.) in East Kalimantan: first growth of living poles of Gliricidia sepium (Jacq.) Walp. and Erythrina lithosperma Miq., and dead poles of Bornean ironwood (Eusideroxylon zwageri Teijs. and Binn.), and experiences with on-farm trials in transmigration settlements. Forestry and Forest Products. Report 8. German Forestry Group, pp. 9-15. Umi Kalsom Yusuf

Erythrina variegata L. Herb. Amb.: 10 (1754); Amoen. acad. 4: 122 (1759). LEGUMINOSAE - PAPILIONOIDEAE

2n =42, 44 Synonyms Erythrina indica Lamk (1786), E. orientalis (L.) Murr. (1787), E. variegata L. var. orientalis (L.)Merrill (1917). Vernacular n a m e s Indian coral tree, variegated coral tree (En). Indian coral bean (Florida), tiger's claw (Am). Arbreau corail, arbre immortel (F). Indonesia: dadap blendung (Sundanese), dadap ayam, (Javanese), dede bineh (Madurese). Malaysia: dedap, cengkering. Papua New Guinea: balbal (Kuanua, Pala), valval (Lamekot), banban (Ugana). Philippines: karapdap (Tagalog), andorogat (Bikol), bagbag (Ilokano). Burma (Myanmar): penglay-kathit. Cambodia: roluohs ba:y. Laos: (do:k) kho, th'o:ng ba:nz. Thailand: thong baan, thong phueak (northern), thong laang laai (central). Vietnam: c[aa]y v[oo]ng nem, h[af]i d[oof]ng b[if] (Annamese), dan ro,(Thuân Hai). Origin and geographic distribution E. variegata is a native of the coastal forests from East Africa, the Indian Ocean Islands, from India, throughout South-East Asia, to the Pacific Islands and the Northern Territory and Queensland in Australia. It has been in cultivation throughout the tropics for so long that its original dispersal as a beach species is now obscure. Uses In India, Malaysia and Indonesia E. variegata is used as live support for betel (Piper betle L.), black pepper {Piper nigrum L.),vanilla (Vanilla planifolia H.C. Andrews) and yam (Dioscorea spp.) vines. When planted as a live fence the more prickly forms are best. In southern India, it is occasionally grown as a shade tree for cocoa and cof-

fee; in Java it is not recommended for this purpose as it is leafless for up to a few months per year. A columnar cultivar is planted in hedges as a windbreak. The leaves are used as green manure and to a limited extent as fodder. Boiled leaves are eaten as a pot-herb. The raw seeds are poisonous but may be eaten after boiling or roasting. The leaves and bark are widely used as cures in many South-East Asian countries. The bark is used as an antipyretic in Burma (Myanmar), in decoction to treat liver problems in China and intermittent fever in Indonesia. A decoction of the bark and leaves is used to treat dysentery in Indonesia; sweetened, it is considered a good expectorant. A decoction of the leaves may also be used to treat mastitis. The bark has also been used to treat rheumatism and to relieve asthma and coughs. The roots and leaves are often employed to alleviate fever in the Philippines. Crushed seeds are used to treat cancer and abscesses in Indo-China, and are boiled in a little water as a remedy for snake bites in Malaysia. In India, the root and bark are called 'paribhadra', one of the reputed drugs ofAyurvedic medicine. The wood is oflittle use, even as firewood, but can be turned into packing-cases. In New Britain, it is used for spears and shields. The wood has been tested as a source of pulp for the paper industry. The fibre is acceptable for pulping, having good length, high flexibility and slenderness ratio and low Runkel's ratio. The light, spongy wood is used in Cambodia as floats for fishing-nets. E. variegata is also planted as an ornamental tree, the leaves of the variegated forms and the flowers being very showy. In New Britain, blackened dried leaves are worn for their scent. Properties Leaves of E. variegata contain per 100 g dry matter 1.5 g N, 1.5 g K, and 0.15 g P. Leaves and seeds have narcotic properties. Alkaloids are present in low concentrations. Seeds contain hypaphorine, erysodine, and erysopine, the leaves and bark the poison erythrinine, acting on the nervous system. Saponins are present in leaves, bark and seeds. Hydrocyanic acid has been found in the leaves, stems, roots, and fruits. The seed contains 0.75% of the free amino acid histidine, an amount only paralleled by E. fusca Loureiro. The wood is white and soft, spongy, fibrous and darker towards the centre. Growth rings are visible. The density ofthe wood is 300 kg/m3. Description Deciduous tree, 3-27 m tall with fluted bole and much branched crown; trunk and

ERYTHRINA

Erythrina variegata L. - 1, habit; 2, leafy branch; 3, inflorescence; 4, flower; 5,pod; 6, seed. branches thick and sappy, armed with large, scattered prickles; bark grey or grey-green, furrowed; young shoots stellate pubescent at first, later glabrous; flowering branches often leafless; in cultivation tree often unarmed. Leaves alternate, trifoliolate; stipules lanceolate, 1-1.5 cm long, caducous; petiole 2-28 cm long, unarmed; rachis 10-12 cm long; petiolule up to 1.5 cm long, at base with globose glandular stipels; leaflets ovate to broadly rhomboid, usually wider than long, 4-25 cm x 5-30 cm, terminal one largest, base rounded or slightly cordate, apex acuminate, entire or sometimes shallowly lobed, thinly coriaceous, green or sometimes strikingly variegated light green and yellow, glabrescent. Inflorescence an axillary, dense raceme 10-40 cm long, ferruginous tomentose, lateral near the top of branchlets; peduncle 7-25 cm long; pedicel up to 1.5 cm long; flowers in groups of 3 scattered along the rachis, large, bright red (occasionally white); calyx eventually deeply spathaceous, 2-4 cm long, glabrescent, red; standard ovate-elliptical, 5-8 cm x 2.5-3.5 cm, more than twice as long as wide,

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shortly clawed, longitudinally conduplicate, recurved, bright red without white veins; wings and keel subequal, 1.5-2.5 cm long, red; stamens 10, monadelphous, 5-7 cm long, vexillar stamen basally connate with the tube for 1 cm, red; pistil with pubescent ovary and glabrous style. Pod sausage-shaped or long cylindrical, 10-45 cm x 2-3 cm, 1-13-seeded, slightly constricted between the seeds, glabrescent, distinctly veined and exocarp bursting irregularly, indéhiscent. Seed ellipsoid to reniform, 6-20 mm x 5-12 mm, smooth, glossy black, purplish or purplish red-brown. Growth and development E. variegata can live to about 100 years. Unpruned trees may attain a height of 15-20 m in 8-10 years. Subsequently, the growth rate slows down, but the main stem continues to increase in diameter. E. variegata forms root nodules and fixes atmospheric nitrogen with Bradyrhizobium bacteria. In general, rooting is superficial, with most roots in the upper 30 cm ofthe soil; older trees, however, root deeper. Other botanical information E. variegata has the typical 'bird flowers' of Erythrina spp.: scentless, strong and elastic to withstand birds hopping about and poking into the flowers. The flowers in the drooping inflorescences are upturned, which prevents the copious nectar from running out. The flowers remain open for 2-3 days, but stop secreting nectar after the morning ofthe first day. Forms with variegated leaves have been classified as botanical varieties; subclassification of the species, however, seems most appropriate at the cultivar level. A cultivar with a columnar habit has been selected. It possibly originated in New Caledonia, from where it spread to other tropical and warm temperate areas, including Hawaii and Florida. It was released in the United States in 1985 as cv.Tropic Coral. Ecology E. variegata is adapted to coastal forests, but is frequently cultivated inland, up to 1200 m altitude. Annual rainfall should exceed 1250 mm. The mean minimum temperature should be about 20°C, the mean maximum temperature about 32°C. As in E. fusca, the seeds float and are dispersed by ocean currents. Propagation and planting E. variegata is usually propagated from large cuttings, 2-3 m long and 5-8 cm in diameter, to ensure that new shoots are above grazing height and to allow fast early growth. Branch cuttings with the terminal bud are sometimes used in India to obtain tall, straight-stemmed trees. Propagation by seed is also possible. Seed germinates in 8-10 days, attain-

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ing a transplantable height of 30-50 cm in 8-10 weeks. In India, a spacing of 8-10 m is used when planting E. variegata for shade in coffee plantations; spacing oflive stakes for betel and pepper is 2-3 m x 2 m. Husbandry When trees are used to support vines, side branches are lopped at intervals of 6-8 weeks, the foliage being used as green manure or fodder. When planted for shade, lower branches are removed immediately after establishment and only a few high branches are allowed to grow. Subsequently, the trees are pollarded once per year in the middle ofthe rainy season. Diseases and pests In Hawaii the trees are attacked by powdery mildew (Oidium sp.), Chinese rose beetle (Adoretus sinicus), mealy bugs (Phenacoccus spp.), mites (Tetranychus cinnabarinus and Polyphagotarsonemus latus). Like other Erythrina spp., it is a potential host of the fruitpiercing moth (Othreis fullonia), the hibiscus snow scale (Pinnaspis strachani), and the carob moth (Ectomyelois ceratoniae) as well as of their predators. In India, larvae of the beetle Raphipodus damage the roots. Yield Yields depend on the pruning system. In India, trees used as support for betel vines yield 15-50 kg fodder per year; shade trees in coffee plantations produce about 100 kg fodder and 25-40 kg wood per year. Genetic resources and breeding E. variegata is included in the Erythrina germplasm collection at Waimea, Hawaii. No breeding programmes are known to exist. Prospects E. variegata is useful as a live fence and source of fodder. It is also a handsome ornamental. It may be used as raw material for the pulp wood industry. Its medicinal value needs further investigation. Literature 111 Hegde, N.G., 1993. Cultivation and uses of Erythrina variegata in Western India. In: Westley, S.B. & Powell, M.H. (Editors): Erythrina in the New and Old Worlds. Nitrogen Fixing Tree Research Reports, Special Issue. Nitrogen Fixing Tree Associaton, Paia, Hawaii, United States, pp. 77-84. |2| Mitra, R. & Srivastava, U.C., 1985. Pharmacognostical study of root and bark of Erythrina indica Lam. Paribhadra. Bulletin of the Botanical Survey of India 27: 75-85. 131 Nguyen Van Thuân, 1979. Leguminosae-Papilionoideae, Phaseoleae. In: Aubréville, A. & Leroy, J.F. (Editors): Flore du Cambodge, du Laos et du Vietnam. Vol. 17. Muséum National d'Histoire Naturelle, Laboratoire de Phanérogamie, Paris, France, pp.

22-24. 141Rotar, P.P., Joy, R.J. & Weissich, P.R., 1986. 'Tropic Coral' tall Erythrina. Hawaii Institute of Tropical Agriculture and Human Resources, Honolulu, Hawaii, United States. 10 pp. I5l Shakya, R., 1988. Indigenous nitrogen-fixing trees in the farmlands of Nepal. In: Withington, D., MacDicken, K.C., Sastry, C.B. (Editors): Multipurpose tree species for small farm use. Proceedings of an international workshop held from November 2-5, 1987, in Pattaya, Thailand. Winrock International Institute for Agricultural Development, Morrington, Arkansas, United States and International Development Research Centre, Ottawa, Canada, pp. 125-130. I6l Soto-Hernandez, M. & Jackson, A.H., 1994. Erythrina alkaloids: isolation and characterization of alkaloids from several Erythrina species. Planta Medica 60: 175-177. 171 Subramanyam, S.V., 1987. Assessment ofutility ofsome pulp wood species of Kerala State based on fibre quality. The Indian Forester 113(6): 427-433. I8l Verdcourt, B., 1979.A manual of New Guinea legumes. Botany Bulletin No 11. Office of Forests, Division of Botany, Lae, Papua New Guinea, pp. 425, 427-428. B. Na-songkhla

Eucalyptus camaldulensis Dehnh. Cat. pi. horti camald., 2nd ed.: 6, 20 (1832). MYRTACEAE

2re = 22 Synonyms Eucalyptus rostrata Schlechtendal (1847). Vernacular n a m e s River red gum, Murray red gum, red gum (En). Indonesia: ekaliptus. Cambodia: pré:ng khchâl' slök sa:. Thailand: yukhalip. Vietnam: b[aj]ch d[af]n [us]c. Origin and geographic distribution E. camaldulensis is the most widely distributed eucalypt. Its natural distribution area covers most of the Australian mainland, ranging from 12°48'S in the tropical Northern Territory to 38°15'S in cool, temperate Victoria. E. camaldulensis is planted in many tropical and subtropical countries and is probably the world's most widely planted tree in arid and semi-arid lands. It is naturalized in many areas. Uses E. camaldulensis is one of the main forestry species for seasonally dry sites in SouthEast Asia. It is widely planted for shade, shelter and amenity purposes and as a source of nectar to produce high quality honey. Wood of planted E. camaldulensis is used mainly for firewood, char-

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coal, poles, posts and paper pulp. It is also used for hardboard, fibreboard and particle board. Logs may be sawn for construction timber (especially for bridges, wharves and ships), railway sleepers, furniture, flooring and packing cases, although the quality is sometimes poor. The bole has potential as a substrate for shiitake mushroom (Lentinus edodes) cultivation and yields a gum which can be used as a dye. Some tropical provenances produce eucalypt oil suitable for medicinal purposes. Production and international trade In addition to extensive but largely unrecorded smallscale plantings worldwide for fuelwood, shade and shelter, over 500 000 ha of plantations had been established by the mid-1970s, mainly in the Mediterranean region using provenances from southern Australia. This figure has now probably doubled due to better adapted provenances from northern Australia being planted in tropical areas. Wood production for domestic consumption is substantial. Wood chips for paper production are exported by several countries in South-East Asia, but statistics for domestic consumption and exports are lacking. Properties Some tropical provenances of E. camaldulensis (e.g. 'Petford') are rich in 1,8-cineole leaf oil and are potential commercial sources of medicinal-grade eucalyptus oil. The medium-weight to heavy timber is hard and durable. The heartwood has a handsome red colour, turning red-brown upon exposure, and is clearly demarcated from the paler sapwood, which is 50-75 mm wide. The texture is moderately coarse, the grain interlocked, straight or wavy, often producing an attractive figure. The density is 700-980 kg/m 3 at 12% moisture content, with samples from natural forest having the higher densities. Density ofplantation-grown E. camaldulensis varies with age, the provenance used and planting site, but does not appear to be closely correlated with rate of growth. Density is positively correlated with charcoal and pulp yield. Provenances from tropical northern Queensland (e.g. 'Petford') produce wood with the highest density and thus the highest yields ofcharcoal and pulp. Mechanical properties of samples from Australia at 12% moisture content are: modulus of rupture 101 N/mm 2 , modulus of elasticity 11 180 N/mm 2 , compression parallel to grain 55 N/mm 2 , shear 15 N/mm 2 , cleavage 89 N/mm radial and 98 N/mm tangential, Janka radial hardness 9745 N, Janka tangential hardness 9525 N and J a n k a end hard-

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ness 10 415 N. The timber is easy to saw despite its high density, and mature material can be seasoned with little degrade. The rates of shrinkage are high: from green to 12% moisture content: 4.4% radial and 8.9% tangential. The heartwood is resistant to termites, but the sapwood is susceptible to attack by Lyctus borers. Preservation is necessary if the timber is to be used in contact with the ground; the heartwood is extremely resistant, the sapwood is permeable to preservatives. The wood of plantation-grown E. camaldulensis often has unfavourable characteristics such as growth stresses, shrinkage on drying, collapse, spiral grain and starch in the sapwood. Its durability is less than that oftrees in natural stands in Australia. Careful post-harvest procedures can ameliorate this. The energy value of the wood is 21 000 kJ/kg. One kg of seed and chaff contains 700 000-800 000 viable seeds, the chaff being ten times heavier than the seed. Description Tree, commonly up to 20 m tall, occasionally reaching 50 m with a trunk diameter of l(-2) m; in open formations with a short, thick bole and a large, spreading crown; in plantations, with a clear bole of 20 m with an erect, lightlybranched crown. Bark smooth, white, grey, yellow-green, grey-green or pinkish grey, shedding in strips or irregular flakes; rough bark may occupy the first 1-2 m of the trunk. Leaves alternate, petiolate, pendulous, (narrowly) lanceolate, 8-30 cm x 0.7-2.0 cm, acuminate, evenly green or greygreen; petiole terete or channelled, 12-15 mm long. Inflorescence an axillary, simple, umbelliform, condensed and reduced dichasium called a conflorescence; umbels solitary, 7-11-flowered; peduncle slender, terete or quadrangular, 6-15 mm long; pedicel slender, 5-12 mm long; flowers regular, bisexual; flowerbuds globular-rostrate or ovoid-conical, divided into a calyx tube or hypanthium (lower part) and the operculum (upper part) which is shed at anthesis; hypanthium hemispherical, 2-3 mm x 3-6 mm; operculum hemispherical, rostrate (northern provenances) to conical (southern provenances), obtuse, 4-6 mm long; stamens numerous, on a staminophore. Fruit a dry thin-walled capsule enclosed in a woody hypanthium, opening with 3-5 strongly exserted valves, hemispherical or ovoid, the hypanthium 3-6 mm x 4-10 mm; disk broad, ascending. Seed minute, about 15 per fruit, smooth, yellow-brown. Seedling with epigeal germination and bilobed cotyledons; first 4-6 pairs of leaves decussate; subsequent leaves alternate. Juvenile leaves al-

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Eucalyptus camaldulensis Dehnh. - 1, habit; 2, flowering branch; 3,fruiting branch. ternate, petiolate, ovate to broadly lanceolate, 13-26 cm x 4.5-8 cm, green, grey-green or bluegreen, slightly discolorous. Growth and development The germination rate is generally high and can reach almost 100%. Lignotubers develop early in the life of northern Australian provenances of E. camaldulensis, but are mostly absent in those from southern Australia. Growth rates vary greatly between provenances and are heavily site-dependent. Seedling growth may exceed 3 m per year for well-adapted provenances on favourable sites. In trials in Peninsular Malaysia using a provenance from Ferguson River (Northern Territory) on three different sites, 4-year-old trees showed a mean annual height increment of 2.3-4.0 m and a mean annual diameter increment of 1.6-3.9 cm. In a trial over 8 years with 51 provenances conducted in Binga, the Philippines, the survival rate ranged from 1-89%, and the average annual growth rate from 1.15-6.84 m in height and from 0.25-6.3 cm in diameter. In trials in Thailand, the mean annual increment was 1.7-4.1 m in height and 1.6-3.9

cm in diameter in the first two years after planting. Time of flowering in natural stands depends on the geography ofa given location. Flowering peaks in summer in southern Australia, in autumn in the far north-west and in winter-spring in the far north-east. In Thailand, some provenances flower almost throughout the year on a range of sites, although September-November is the peak period. Pollination is mainly by insects but also by birds and small mammals. Seeds ripen about six months later. In Thailand, peak flowering corresponds with seed ripening in April-May. In South-East Asia, the period from planting to production of the first seed crop may be as short as three years. In Thailand, E. camaldulensis may start flowering when 16-38 months old, but 24-28 months is common. Eucalypts do not develop resting buds and grow whenever conditions are favourable. Other botanical information There is considerable morphological variation within E. camaldulensis, which is not surprising given its wide geographic distribution. Six varieties have been described, but this division has been largely ignored because of difficulties in identification. The northern and southern provenances are sometimes accommodated in two varieties: var. camaldulensis and var. obtusa Blakely, respectively. Var. camaldulensis has rostrate opercula, while var. obtusa has obtuse or rounded ones. However, the variation in this character seems to change gradually with the location. E. camaldulensis is closely related to E. tereticornis Smith. The latter can be distinguished by its taller and more steeply branched habit, its acutely conical opercula and the black, rough-coated seeds. Where both species grow naturally, as in eastern Victoria and Queensland, hybridization and subsequent introgression occurs. Several populations in far northern Queensland, previously identified as E. tereticornis, show several characteristics of E. camaldulensis and are now considered a separate subspecies ofthe latter called subsp. simulata. Among them are the fast-growing provenances of 'Laura River', 'Palmer River' and 'Walsh River' that are widely used in South-East Asia. Natural hybrids between E. camaldulensis and E. alba Reinw. ex Blume are also reported, while in plantations hybridization with E. grandis W. Hill ex Maiden occurs. Ecology Under natural conditions, E. camaldulensis occurs typically along watercourses and on floodplains, very occasionally in southern Aus-

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tralia extending to hills or ranges, usually in open forest and woodland, at 20-700 m altitude. It grows under a wide range of climatic conditions, from temperate to hot and from humid to arid. Annual rainfall in natural stands varies from 250-2500 mm, but planted trees can survive in areas with as little as 150 mm annually. In arid regions, it depends on the presence of a high water table or seasonal flooding for survival. The length of the dry season may vary from 0-8 months and the rainfall distribution varies from a winter maximum in southern regions to a monsoon type with summer rains in northern areas. Mean minimum temperature of the coldest month ranges from 3-22°C, mean maximum temperature of the hottest month from 21-40°C and mean annual temperatures from 13-28°C. In general, E. camaldulensis tolerates up to 20 frosts per year, but does not tolerate temperatures below -10°C. The optimum temperature for germination is 32°C, but a wide range is tolerated. E. camaldulensis occurs on a variety of soils, commonly on sandy and silty alluvial soils, but occasionally on heavy clays in southern Australia; it is also found along the borders of salt lakes. It is not adapted to calcareous soils, except for a few populations in southern and western Australia growing on shallow soils over limestone. Provenances may differ considerably in frost tolerance, fire resistance and salt tolerance. Propagation and planting Selection of the proper genetic material for particular planting conditions is of paramount importance. E. camaldulensis is usually propagated by seed. As a ruleof-thumb, 1 kg of seed is sufficient to provide plants for 100 ha at a spacing of 3 m x 2 m and the typical seedling recovery rate of 25%. Seed is best stored dry (5-8% moisture content) in airtight containers at 3-5°C. Viability will be maintained for several years and is still about 30% after being stored for seven years. No pre-sowing treatment is required. The fine yellow-brown seed and chaff are sown together under shade in a well-drained and sterilized medium and covered very sparingly with sand. After 4 days, seed has germinated and shade should be reduced. When 2 pairs of leaves have developed, seedlings are pricked out into containers such as polythene bags filled with a sterilized potting mix. Shading is needed for the first week after transplanting, thereafter plants should be fully exposed. A polythene bag size of 15 cm x 5 cm proved most economic in Nigeria. Direct sowing in polythene bags or in open nursery beds for the production of bare-rooted planting stock is

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also practised. Growth is fast under tropical conditions, and plants can be planted out after 3 months, occasionally after 6 weeks, when they are 30 cm tall. Excessive watering and shade often result in damping-off and in seedlings becoming too tall and weak for easy transplanting. E. camaldulensis is suited to mass vegetative propagation. Cuttings from juvenile shoots (i.e. below the 10th node) root readily in about 30% of the genotypes. A major reforestation project in Morocco is based entirely on cuttings ofE. camaldulensis. In South-East Asia, propagation by cuttings is an integral component of breeding programmes. Elite trees are selected in young plantations (5 years old) and felled or girdled to promote coppicing. Coppice shoots of about 1 m long are collected and divided into pencil-sized cuttings with two leaf pairs. Half of the leaf blade is then trimmed and the cuttings are dipped into a hormone preparation and planted in pots under mist and shade. Rooted cuttings are usually planted in nurseries to provide further shoots. Methods of in vitro propagation have been developed. Spacing varies with the management system from community planting around homes, villages and roads to closely-spaced commercial plantations - and depends on the end-products required. For firewood, spacings as close as 2 m x 2 m are used; for pulpwood, a spacing of 3 m x 2 m is often applied. Wider spacings o f 4 m x 2 m o r 5 m x 2 m are recommended when larger trees are the objective. In plantations, E. camaldulensis has a comparatively narrow crown and pendulous leaves which allows light to reach the forest floor. This is favourable for intercropping with food crops but also promotes weed growth. A spacing of 5 m x 2 m is recommended to allow intercropping during the first three years. Application of 100 g of NP or NPK (3:2:1) fertilizer to each tree at planting to assist establishment and early growth is common. In trials in Thailand, survival was 80-90% 12 months after planting. Husbandry Poor competition ability with weeds and the development of an open crown imply frequent weeding, up to 3 times per year, until the canopy closes 3-5 years after planting. Inadequate weed control may lead to complete failure of the plantation. Intercropping may facilitate proper weed control. A thinning to less than 700 stems/ha at 5 years provides posts, poles, fuelwood and pulpwood, leaving the better trees for the production ofe.g. sawn timber after 10 years. Crown dieback during the dry season as a result of boron deficiency is prevalent in parts of Africa,

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Asia and South America and must be corrected. A dosage of 10-20 g of borax per tree is recommended, depending on soil type. All fast-growing provenances tested coppice well. The rotation may be as short as 3-5 years for small-sized pulpwood in Thailand and Vietnam, but is generally 8-10 years. In Israel, maintaining a plantation for 5 successive 10-year coppice rotations has been successful, but in general 2-3 coppice rotations of 10-12 years are feasible. Reduction ofthe number of coppice shoots on a stool is a most important and time-consuming operation in coppice management. In Nepal, a single reduction at 3-6 months to one shoot per stump is recommended. Competition from eucalypts can severely reduce yields of interplanted crops. In an experiment in northern Nigeria, pearl millet (Pennisetum glaucum (L.) R. Br.) yields were reduced up to at least 18 m from a eucalypt shelter-belt and pruning the roots ofthe eucalypts down to 1m significantly increased millet yields. Diseases and pests In the nursery, E. camaldulensis is susceptible to various fungi causing damping-off and leaf diseases. Proper hygiene and watering sparingly minimize damage. Insects (e.g. termites and aphids) and rodents may be troublesome, and both physical and chemical control measures are used. In Australia, natural stands and plantations are affected by many fungi and insects. On suitable sites outside Australia, E. camaldulensis is relatively free of diseases and pests. Stem canker and leaf diseases proliferate where rainfall and humidity are much higher than encountered in the natural habitat. In South-East Asia, E. camaldulensis may be defoliated by fungi including Cylindrocladium spp. during the rainy season. The most susceptible provenances suffer mortality and general decline, but well adapted provenances (e.g. 'Katherine') are little affected. In parts of Africa and Asia, termites attack seedlings and young trees and must be chemically controlled. In Africa, the Eucalyptus snout beetle (Gonipterus scutellatus), of Australian origin, feeds on young shoots but is controlled biologically; moribund or newly-felled trees may become infested with an Australian stem borer or the longicorn beetle (Phoracantha semipunctata). Harvesting E. camaldulensis is usually grown on a short rotation and clear-felled at an age that maximizes production for a particular end-use. Generally, this is small-diameter material for fuelwood or pulp. The felling season affects coppice regeneration. Felling during the dry season delays

sprouting and increases the risk ofthe stump drying out. Felling by saw to give a clean-cut short stump with minimum bark damage is best. In coppice systems e.g. in Nepal, some stems are sometimes left uncut as standards. This practice is recommended to produce wood of a range of diameters suitable for various products. Yield Very high productivity is possible under favourable conditions: a mean annual increment of 70 m 3 /ha of four-year-old trees planted at 3 m x 2 m on a fertile site with high water availability has been recorded in Israel. However, such conditions are seldom met. In the drier tropics, yields of 5-10 m 3 /ha per year on a 10-20-year rotation are common, whereas in moister regions up to 30 m 3 /ha per year may be achieved on 7-20-year rotations. In southern Vietnam, mean annual increments of 12 m 3 /ha over 4 years have been recorded, which can reach 20 m 3 /ha for the best adapted provenances. Coppice rotations give higher yields than the initial seedling rotation (e.g. 25-30 m 3 /ha per year versus 17-20 m 3 /ha per year in Turkey) and the length of the rotation may be adjusted accordingly. Handling after harvest End-splitting of roundwood may be reduced by felling during winter months. For sawn timber production in Pakistan, it is recommended to fell in October, convert immediately into 70 mm quarter-sawn planks, carefully stack in a well-ventilated room and then top load each stack, in order to reduce defects. Genetic resources Both primary and secondary centres of diversity hold vast genetic resources ofE. camaldulensis. It is often impossible to trace the origin of seed used for plantations, so the extent ofgenetic variation available in various areas is uncertain. Systematic introduction of appropriate seedlots from native Australian stands is highly recommended to ensure that a wide genetic variation is used for selection and breeding. In Australia two groups of provenances are distinguished: a northern tropical group and a southern temperate group. The better-performing tropical provenances, such as 'Petford' and 'Katherine' are generally the most sought-after for breeding programmes in South-East Asia. The Australian Tree Seed Centre (ATSC) provides both single-tree and bulk provenance collections of E. camaldulensis for breeding programmes. A well-documented, 400-tree collection from the Petford region is presently available at ATSC along with accessions from many other areas. Breeding The ideal commercial tree should have good vigour and resistance to diseases and

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pests, a straight single bole, drought tolerance, good coppicing ability, high pulp yield (lightcoloured timber), thin branches and good selfpruning ability, and a thin bark. Although seed availability of climatically adapted northern Australian provenances has increased, supplies are still insufficient to meet demand in South-East Asia. Consequently, a number of countries in the region support selection and breeding programmes, for instance the comprehensive programme in Thailand is based on seed from local trees and 308 seedlots from northern Australia including 200 from Petford. These accessions have been planted in orchards in 4 locations with different environments; they will be thinned progressively and supply improved seed and coppice material. Prospects E. camaldulensis is one of the best performing trees in the seasonally dry tropics for an impressive array of end-products. The success ofE. camaldulensis as an exotic is attributed to its superiority to other trees in the production of wood for firewood, charcoal and other purposes on infertile dry sites, its tolerance of drought and high temperature combined with rapid growth when water is available, its tolerance of periodic waterlogging and soil salinity and its fair tolerance offire and frost. Its productivity and versatility can be enhanced by breeding programmes now under way in South-East Asia and elsewhere. With careful selection of provenances for specific sites, E. camaldulensis is expected to gain importance in South-East Asia. Literature 111 Blakely, W.F., 1955. Akey to the eucalypts. 3rd Edition. Forestry and Timber Bureau, Canberra, Australia. 359 pp. 121 Chippendale, G.M., 1988. Myrtaceae - Eucalyptus, Angophora. In: George, A.S. (Editor): Flora of Australia, Vol. 19.Australian Government Publishing Service, Canberra, Australia, pp. 327-329. I3l Doran, J.C. &Brophy, J.J., 1990. Tropical red gums a source of 1,8-cineole-rich Eucalyptus oil. New Forest 4: 157-178. 141Eldridge, K., Davidson, J., Harwood, C. & van Wijk, G., 1993. Eucalypt domestication and breeding. Clarendon Press, Oxford, United Kingdom, pp. 60-72. 151 Jacobs, M.R., 1981. Eucalypts for planting. 2nd Edition. FAO Forestry Series No 11. Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 369-381. 161Kijkar, S., 1991. Handbook: producing rooted cuttings of Eucalyptus camaldulensis. Association of South East Asian Nations(ASEAN)Canada Forest Tree Seed Centre Project, MuakLak, Saraburi, Thailand. I7l Midgley, S.J., El-

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dridge, K G . & Doran, J . C , 1989. Genetic resources of Eucalyptus camaldulensis. Commonwealth Forestry Review 68: 295-308. I8l Onyewotu, L.D.Z. & Stigter, C.J., 1995. Eucalyptus its reputation and its roots. Millet and a eucalyptus shelterbelt in northern Nigeria. Agroforestry Today 7: 7-8. J.C. Doran &W. Wongkaew

Eucalyptus tereticornis J.E. Smith Spec. bot. New Holland 1:41 (1795). MYRTACEAE

2w=22 Synonyms Eucalyptus subulata Cunn. ex Schauer (1843), E. insignis Naudin (1891), E. umbellata (Gaertner) Domin (1928) non Desf. Vernacular n a m e s Forest red gum, blue gum (En). Cambodia: pré:ngkhchâl' sloktôxh. Origin and geographic distribution E. tereticornis has an extensive natural distribution in a long strip about 100 km wide, from southern Papua New Guinea and the northern tip of Queensland to southern Victoria along the east coast ofAustralia. The Great Dividing Range separates its area of distribution from that of E. camaldulensis Dehnh. It was one of the first eucalypts exported from Australia and is now cultivated throughout the tropics, on an especially large scale in India and Brazil. U s e s E. tereticornis is used for reforestation, shelter-belts and shade. The wood is a major source of fuelwood, charcoal, and timber for local use. It is hard, strong and durable and is also used for light and heavy construction, railway sleepers, bridges, wharves, piles, poles, mining timber, pulpwood, hardboard and particle board. E. tereticornis is a major source of pollen and nectar, producing a caramel-flavoured honey. The leaves are one of the sources of eucalypt oil. The essential oil and the tannin from wood and bark are not utilized commercially. Production a n d international trade E. tereticornis is among the four most commonly planted Eucalyptus species throughout the world. It is, therefore, most likely that saw and veneer logs and pulp of E. tereticornis are internationally marketed, but specific information is lacking. In Vietnam approximately 16000 ha have been planted, in India over 500000 ha and in Brazil about 250 000 ha. Properties The sapwood is grey to creamcoloured and fairly well demarcated from the pale

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to dark red heartwood, ofeven texture with wavy or interlocked grain, making it somewhat difficult to finish. At 12% moisture content the density of the wood from plantations is considerably lower (e.g. 730-800 kg/m3, Madagascar) than that from natural forests (910-1010 kg/m\ Australia). The energy value ofthe wood is 20000-22 000 kj/kg. The shrinkage of wood during seasoning is high and ithas a strong tendency towarp. In Australia, the wood is one of the most resistant to marine borer attack, butit failed after 2.5-10 years atthe Pacific coast ofthe United States. Sapwood is susceptible toLyctus. Thewood contains 0.5% essential oil and 6-12% tannin; the bark contains 3-15% tannin. The wood yields avery good quality PulpCommercial seed contains 320-600 viable seeds per gram. About 90% of commercial seed is chaff consisting mainly ofunfertilized ovules. Description A large tree, up to 50m tall, bole straight andclear for more than one-half, upto2 m in diameter. Bark decorticating over the whole

Eucalyptus tereticornis J.E. Smith - 1, habit; 2, flowering branch; 3,juvenile leaf;4, adult leaf; 5, flower buds; 6, fruits.

trunk inlarge plates orflakes toleave a smooth or mat, mottled surface, white, grey or grey-blue; some rough, dead bark is frequently retained at the base ofthe tree. Leaves alternate, thick; petiole 13-24mm long, terete or channelled; blade narrowly lanceolate to lanceolate, 10-20 cm x 1-2.7 cm,acuminate, glabrous, shiny green, concolorous with venation conspicuous, pinnate, lateral veins angled at40-50° tothemidrib. Inflorescence an axillary, simple, condensed and reduced, umbelliform dichasium, usually called a conflorescence; umbels solitary, 7-11-flowered; peduncle terete orangular, 7-25mmlong; pedicel 3-10mm long; flowers regular, bisexual, white; flower buds clearly divided into a calyx tube or hypanthium (lower part), and operculum (upper part, formed by thecalyx lobes andpetals) which is shed atanthesis; hypanthium hemispherical, 2-3mmx4-6 mm; operculum acutely conical, 8-13 mm x 4-6 mm; stamens numerous, ona staminophore, erect and all fertile, anthers versatile, oblong, opening by longitudinal slits; ovary inferior, with many ovules. Fruit a dry,thin-walled capsule enclosed in a woody hypanthium, opening with 4-5 strongly exserted valves, subglobular toovoid, 5-7mm x 4-8 mm,with broad, steeply ascending disc. Seed rough, brown-black. Seedling with epigeal germination, at first with square stem; cotyledons bilobed; leaves decussate; juvenile leaves opposite for 2-3 pairs, then alternate, petiolate, ovate,6-16 cm x 5-6 cm, dull, green to blue-green, slightly discolorous. Growth and development In plantations, E. tereticornis starts flowering when 2-6 years of age; 2-month-old seedlings have been observed flowering in Brazil. Small clusters of white flowers appear every year, butheavy blooming occurs only once every 3-4 years. In a 3-year-old plantation in Java the mean annual increments in height andin diameter were 4.2mand3.5cm,respectively; in 4-year-old trials in Peninsular Malaysia they were 2.0-3.6 m and 1.7-3.3 cm; in 1-year-old trials in Thailand, 1.7-6.5 m and 2.5-6.8 cm, depending onprovenance andsite.On a poor site in Papua NewGuinea the annual increments were 3.3 m and 2.1 cm.On favourable sites in Indonesia trees attain a height of35 min 10 years, onpoorer sites 15-18 m.Thepresenceof ectomycorrhizal associations inE. tereticornis has been assumed, buthas not yetbeen confirmed. Other botanical information E. tereticornis is closely related to E. camaldulensis and natural hybrids are sometimes encountered. E. camaldulensis differs byits usually smaller habit, the al-

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ternate juvenile leaves, the rostrate to obtusely conical operculum and the smooth seed. Many early introductions of E. tereticornis were derived from very few original seed trees. The inbred landrace 12ABL is thought to be descended from a single tree in Madagascar and is widely planted in West Africa; Eucalyptus C is a landrace or possibly a hybrid from Zanzibar and is planted in East Africa. 'Mysore Gum', which represents about half of the eucalypt plantations in India, is believed to originate from a few trees in the Nandi Hills (Andhra Pradesh, India). It is also known as 'eucalyptus hybrid' or 'Mysore hybrid', although it is now considered to be mainly E. tereticornis, with only occasional evidence of hybridization with E. robusta J.E. Smith and probably E. camaldulensis. Ecology E. tereticornis occurs from 6-38°S latitude and climatic conditions in its natural range vary greatly. Rainfall distribution varies from monsoonal with marked dry and wet seasons in southern Papua New Guinea, a summer rainfall climate with a very dry winter in Queensland, and an even distribution of rainfall in southern Queensland, to a dry summer and cold, wet winter in eastern Victoria. Mean annual rainfall is (500-)800-1500(-3500) mm with a dry season of up to 7 months. E. tereticornis is mainly found on alluvial flats in cooler and drier areas, on lower hill-slopes in higher rainfall areas, and on upper slopes and plateaux in the tropics. Its altitudinal range is from near sea level up to 900 m in Australia and up to 1800 m in Papua New Guinea. The mean maximum temperature of the hottest month is 22-32°C, the mean minimum temperature ofthe coldest month 2-12°C. Up to 15 days of frost are tolerated. In southern China and Pakistan adapted selections are reported to survive -7°C. Soil conditions seem to limit its natural occurrence. It is not found on heavy clay, acid or dry, shallow soil, preferring deep, well-drained, fairly light-textured alluvial soil. E. tereticornis can stand occasional flooding and in India, it is highly resistant to waterlogging during the first year, although in natural forest it is rare under such conditions. Propagation and planting E. tereticornis can be propagated by seed or cuttings. For transport of seed, it may be worthwhile to separate seed and chaff, e.g. by sieving. Seed can be stored for several years if air-dried and stored in the dark in sealed containers at a temperature of 1-4°C. The germination rate can be maintained at an acceptable level for 1-2 years by storing the seed in un-

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sealed containers at room temperature. The germination rate ofEucalyptus spp. is commonly given as the number of plants obtainable from 1 g of seed (with chaff), e.g. 480 for_E. tereticornis, corresponding with about 80% germination. The most common and effective way to raise seedlings is to sow the small and untreated seed in trays under light shade in a sterilized medium (e.g. soil or vermiculite). A sowing rate of 10-15 g/m2 is recommended, but the sowing density should be decreased in areas with a high risk of damping off. Seed germinates in 4-14 days. The young seedlings are pricked out and transplanted into containers when 2-4 pairs of leaves above the cotyledons have developed. An additional 3-6 months in the nursery is required to obtain seedlings of plantable size. Direct sowing in containers is also practised, but it is very difficult to sow only a few of the minute seeds per container. Watering is done by spraying. Bare-rooted planting stock may be used in areas with a humid climate, while stumps have proved satisfactory in India. Recorded spacings at planting are 2 m x 2 m (East Java), 2.7 m x 3.0 m (Peninsular Malaysia), 1-2 m x 1-2 m (the Philippines) and 2.7 m x 2.7 m (Papua New Guinea). In Papua New Guinea, growth is satisfactory on infertile and poorly drained grassland and on copper mine tailings, provided that N, P and K fertilizer is applied. Vegetative propagation using branch cuttings of 2-3-year-old saplings and from suckers has been successful. Husbandry Clean weeding is extremely important for good establishment and early canopy closure. In grasslands with Themeda triandra Forssk. and Imperata cylindrica (L.) Raeuschel in the Philippines, weeding is done every 3-4 months to obtain a seedling survival of 80-100%. For the production of firewood and pulpwood, rotations of 7-12 years are applied. Thinning is done 2-5 years after planting. E. tereticornis coppices vigorously and regeneration by coppice is commonly practised. After the original seedling crop, 2-4 coppice crops can be harvested. After cutting, two-several coppice shoots remain after 'self-thinning'. These are thinned to 1-3 coppice shoots per stool at the age of 18 months. For the production of construction wood the rotation is 20-30 years with a final density of 70-120 trees/ha. In Papua New Guinea, ploughing and mounding helps to mineralize sufficient soil nutrients to enable adequate growth. The initial planting density is 1300-1600 trees/ha, reduced to 900 trees/ha after 5 years. Resprouting after fire was observed in the

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Philippines, but fire killed 80% of the seedlings planted six months earlier. Diseases and pests E. tereticornis is fairly free from diseases and pests. Damping-off in the nursery may be a serious problem, but reducing shade and humidity can prevent major damage. In the Solomon Islands, dieback attributed to the coreid bug Amblypelta cocophaga was observed in 3-4month-old plantings. Resistance to termite attack is generally very high, but Neotermes insularis may attack the tree in its natural distribution area. Harvesting When harvested the stool should be lower than 12 cm to allow for the development of stable shoots. Yield In East Java, the mean annual increment over 10 years is 27 m 3 /ha for a trial plantation at 800 m altitude. On good sites, 18-25 m 3 /ha may be generally expected. A mean annual increment of 30-35 m 3 /ha for the hybrid of E. tereticornis x E. grandis W. Hill ex Maiden was recorded over 6-7 years on savanna sands in Congo. Genetic resources Provenances have been conserved ex situ in Congo, Nigeria, Zambia, Fiji and Bangladesh. Seed is commercially available in Australia from a great number of provenances. The 'Mysore hybrid' or 'eucalyptus hybrid', used in most plantations in India, is a complex of landraces of E. tereticornis, suspected to have originated from a restricted genetic base of Australian trees, and hybrids with E. robusta or E. camaldulensis. Performance in plantations has left much to be desired due to the great variability within stands and slow growth compared with pure species of appropriate provenance. Breeding An important effort has been put into progeny and provenance research particularly in the tropical provenances from north-eastern Queensland. Eucalyptus species often hybridize readily. Natural populations with intermediate characteristics between E. tereticornis and E. camaldulensis occur in north-eastern Queensland. These two species also hybridize spontaneously in plantations and artificial crossing in India showed a striking degree ofhybrid vigour; the hybrid, designated as F.R.I.-4 and F.R.I.-5, produced three times the wood volume ofE. tereticornis at 4 years of age. E. tereticornis x E. grandis (South Africa) does not have the hybrid vigour, but is resistant to pink disease (Corticium salmonicolor) whereas E. grandis is not. Prospects Its rapid growth and its adaptability to a variety of environmental conditions make E. tereticornis very promising to be included in trials

in South-East Asia on a wider scale. However, testing and selection of locally adapted provenances should receive high priority if E. tereticornis is to be utilized to its full potential. Literature 111Chippendale, G.M., 1988. Eucalyptus. In: George, A.S. (Editor): Flora of Australia. Vol. 19.Australian Government Publishing Service, Canberra, Australia, p. 324. 12 Eldridge, K., Davidson, J., Harwood, C. & van Wijk, G., 1993. Eucalypt domestication and breeding. Clarendon Press, Oxford, United Kingdom, pp. 139-143. 131 Fenton, R., Roper, R.E. & Watt, G.R., 1977. Lowland tropical hardwoods - an annotated bibliography of selected species with plantation potential. External Aid Division, Ministry of Foreign Affairs, Wellington, New Zealand, pp. ETe 1-ETe 38. 141 Jacobs, M.R., 1981. Eucalypts for planting. 2nd Ed. FAO Forestry Series No 11. Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 494-498. I5l Lamb, D., Johns, R.J., Keating, W.G., Ilic, J. & Jongkind, C.C.H., 1993. Eucalyptus L'Hér. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors): Plant Resources of South-East Asia No 5(1): Timber trees: Major commercial timbers. Pudoc Scientific Publishers, Wageningen, the Netherlands, pp. 200211. 161 Penfold, A.R. & Willis, J.L., 1961.The eucalypts: botany, cultivation, chemistry and utilisation. Hill, London, United Kingdom. 551 pp. 171 Pinyopusarerk, K., 1989. Growth and survival of Australian tree species in field trials in Thailand. In: Boland, D.J. (Editor): Trees for the tropics; growing Australian multipurpose trees and shrubs in developing countries. ACIAR Monograph No 10. Australian Centre for International Agricultural Research, Canberra, Australia, pp. 109-127. E. Boer

E u c a l y p t u s u r o p h y l l a S.T. B l a k e Austrobaileya 1(1):7 (1977). MYRTACEAE

2n = 22 Synonyms Eucalyptus alba auct., non Reinw. ex Blume,E. decaisneana auct., non Blume. Vernacular names Timor white gum, Timor mountain gum (En). Indonesia: ampupu, popo (Indonesian, Timor), palavao preto (Portugese, East Timor).Vietnam: b[aj]ch d[af]n d[or]. Origin and geographic distribution The natural distribution ofE. urophylla is confined to the eastern part ofthe Lesser Sunda Islands (Bali and

EUCALYPTUS

Nusa Tenggara), occurring principally on the islands of Timor, Alor and Wetar with fewer occurrences on Adonara, Lomblen, Pantar and the eastern parts of Flores. The natural range extends about 500 km between longitudes 122-127°E and latitudes 7°30'-10°S. It has been introduced to Java in 1890 and in 1919 to Brazil (as E. alba). In 1966, it was introduced to Australia and since then to many other countries, notably Papua New Guinea, Malaysia, China, Cameroon, Congo, Ivory Coast, Gabon, Madagascar and French Guiana. Uses E. urophylla is increasingly used in reforestation programmes and is economically important for wood production. It makes satisfactory fuelwood and charcoal. In Timor, the wood is used for heavy construction and bridging, elsewhere also for framing and flooring. Round wood is used for building poles and fence posts. It is particularly suitable as a source ofmid-density to low-density eucalypt fibre for pulp and paper production. The bark has a tannin content of over 10%, but is not used commercially. Properties The wood of E. urophylla is moderately durable. The heartwood is pinkish-brown to red-brown, and contains little gum. The basic density is in the range of 540-570 kg/m 3 , which is comparatively light compared to other Eucalyptus species. The wood is fairly easy to saw. Fibres are relatively short, 0.7-1 mm, and the wood is suitable for bleached chemical pulp and has a good pulp yield ofabout 50%. On average, there are 210-470 viable seeds per g ofuncleaned seed. Production and international trade No statistics on trade are available. Extensive plantations ofE. urophylla and its hybrids have been established in Brazil, China, Congo and elsewhere. The most commonly planted hybrid is E. grandis W. Hill ex Maiden xE. urophylla. Description Evergreen tree up to 45(-55) m tall, in unfavourable environments a gnarled shrub; bole usually straight, branchless for up to 30 m, up to l(-2) m in diameter. Bark variable depending on available moisture and altitude, usually persistent and subfibrous, smooth to shallowly and closely longitudinally fissured, redbrown to brown, sometimes rough especially at the base ofthe trunk. Juvenile leaves subopposite, stalked, broadly lanceolate, 10-15 cm x 5-8 cm, discolourous, lateral veins just visible, at 50-70° to the midrib; adult leaves phyllodinous, subopposite to alternate, long stalked (12-30 mm), broadly lanceolate and abruptly narrowed into a short tip or lanceolate and tapering into a long drip tip,

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I ,/

Eucalyptus urophylla S.T. Blake - 1, flowering branch; 2, fruiting branch. 12-20 cm x 2-5 cm, lateral veins visible, at 40-50° to the midrib, dark green above, paler green below. Inflorescence an axillary, simple umbelliform condensed and reduced dichasium called a conflorescence; umbels solitary, 5-8-flowered; peduncle somewhat flattened, 8-22 mm long; pedicel angled, 4-10 mm long; flowers regular, bisexual; flower buds ellipsoid to obovoid, shortly pointed to rotund, 10-14 mm x 6-10 mm, divided into a calyx tube or hypanthium (lower part) and an operculum (upper part) which is shed at anthesis; stamens numerous, on a staminophore. Fruit a dry thin-walled capsule enclosed in a woody hypanthium, opening with 3-5 included to partly exserted valves, obconical to cup-shaped, 6-14 mm x 7-18 mm; disk almost flat to obliquely depressed. Seed small, 4-6-angular to more or less semi-circular, black. Seedling with epigeal germination; cotyledons usually bilobed to about the centre; first 5-7 pairs of leaves opposite, subsequent pairs subopposite. Growth and development Mature seed germinates readily under favourable conditions and does not require pregermination treatment. Seed-

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lings usually reach 25 cm in height in 10-12 weeks. In conditions of high relative humidity, young seedlings may be susceptible to dampingoff. E. urophylla retains its leaves during the dry season, and grows actively when moisture and temperature conditions are favourable, with a strong apical dominance. In dry locations and on shallow soils on mountain ridges, apical dominance is less pronounced and plants may develop into shrubs. In Thailand, early growth of two different provenances during the first year was 2.4-6.2 m in height and 3.9-7.4 cm in diameter. In Peninsular Malaysia, growth during the first four years was 1.7-3.5 m/year in height and 2.0-3.9 cm/year in diameter. In East Java, a trial of trees aged 7 years and 9 months showed a mean height of27 m and a mean diameter of 22.8 cm. Very rapid initial growth has been reported from the Solomon Islands, but the trees remained thin-stemmed and developed a thin canopy, most probably because the climate was too humid. In general, progenies from low altitudes in Flores, Alor and Timor grow fastest. Flowering usually starts within 2 years after planting and seeds are produced abundantly by 4 years of age. In Brazil, flowering of two-month-old seedlings has been observed occasionally. In its natural habitat, peak flowering of E. urophylla is strictly tied to the rainy season in J a n u a r y March. Pollination is by insects. Fruits reach maturity about 4 months after flowering, in May-July(-August). Other botanical information E. urophylla appears to be one of the most variable of all eucalypts, with considerable variation in morphological features such as adult leaf size and expression of a drip tip, bud characteristics, fruit size and shape. There are also differences between the seedling, juvenile, intermediate and adult leaves. The extreme variation in bark characteristics appears to be associated with differences in available moisture and altitude. Boles are mainly smooth at lower altitudes and under drier conditions. Smooth boles with rough bark at the base are found below 1000 m altitude in Alor and Flores, at 1000-2000 m in Timor the boles are usually entirely covered with rough bark, above 2000 m in moist conditions the bark is usually subfibrous. Recent analyses indicate that specimens from high altitude sites in Timor and from dry sites in Wetar are distinct from the residual E. urophylla. These have been designated E. orophila L.D. Pryor and E. wetarensis L.D. Pryor respectively.

E. urophylla has been distinguished as a separate species only recently. It has been widely cultivated under the name E. alba Reinw. ex Blume or as E. decaisneana Blume. In Java, the name E. platyphylla F. Muell. was used for E. alba. As a consequence, considerable confusion exists about the true nature of several provenances. Where natural populations of E. urophylla meet those of E. alba, hybrids are frequently encountered and introgression of characters may take place. This enhances the confusion about true identities of provenances. E. alba is a smaller tree of poor shape, the adult leaves are generally broader (2-5 cm), concolourous, and lack the characteristic drip tip, while its fruit is hemispherical to obconical and 4-7 mm x 5-8 mm. Hybrids may be recognized by their white, smooth trunk, their larger and less numerous leaves but the extreme variability in the bark characteristics of E. urophylla can make identification ofhybrids difficult. Ecology E. urophylla (including E. orophila and E. wetarensis) has the largest altitudinal range of any eucalypt, extending from 1000-2960 m in Timor, from 70-800 m in Wetar and from 3001100 m in Flores and the smaller islands to its east. It is frequently found as the dominant species in secondary montane forest. At lower altitudes and in drier, exposed locations usually below 1500 m, it is often replaced by E. alba. The natural range ofE. urophylla is in the humid and sub-humid climatic zones.At about 400 m altitude the mean maximum temperature of the hottest month is 27-30°C, which may drop to only 15-21°C at 1900 m. Mean maximum temperature of the coldest month is 8-12°C. In Timor many of the E. urophylla forests occur at about 1000 m altitude, where mist and fog are common, annual rainfall is 1300-2200 mm, and the dry season is (2-)3-4 months. On other islands, drier conditions prevail with rainfall of 600-1500 mm, and a dry season of5-8 months. E. urophylla grows on mountain slopes and in valleys. It develops best on deep, moist, well-drained, acidic or neutral soils derived from volcanic or metamorphic rock. It is also commonly found on basalts, schists and slates, but rarely on limestone. Propagation and planting Nursery establishment is generally by sowing untreated seed in germination beds. Mature seed germinates readily in 7-12 days and does not require any pretreatment. Damping-off can be prevented by reduced watering and shade, and allowing ventilation. The seedlings are transplanted into polythene bags

EUCALYPTUS

when they have developed 2 pairs of leaves. The potting medium is usually a freely draining mixture of loam and sand. Seed may also be sown directly into containers and thinned out after germination. Seedlings are planted out in the field when they reach a height of about 25 cm, 10-12 weeks after sowing. In Brazil, E. urophylla or hybrids of E. urophylla and E. grandis are raised using rooted cuttings derived from stump sprouts. After coppicing, when the new sprouts are 60-80 cm long, they are removed and divided into cuttings with two pairs of leaves. The leaves are treated with a fungicide. The cuttings are dipped in a rooting hormone and then set to a depth of4 cm in polythene bags filled with subsoil clay. They are kept under 50% shade and intermittent mist spray for 30-40 days. At this stage, roots have formed and the cuttings are moved to full sunlight and 1 g of complete fertilizer is added to each bag. They are planted out when 70-80 days old. After culling clones with poor rooting capacity, 80% rooting is generally achieved in commercial production. Tissue culture has proved successful on an experimental scale in Indonesia; the expiants are taken from 3-week-old material. The hybrid E. urophylla x E. grandis has been planted using tissue cultured plants on a pilot scale in Guangdong Province, China. Intensive site preparation by ploughing is beneficial; on compacted sites, deep ripping may also be used. NPK fertilizer is applied in each planting hole. Spacing varies with the purpose of the plantation. For pulpwood, 3 m x 2 m is commonly used, for fuelwood or poles planting may be closer. Husbandry Plantations are invariably established using containerized seedlings or cuttings. It is essential to keep the planting site weed-free, at least until the trees reach 6 months of age, since eucalypts are highly sensitive to competition. After 6 months, their dense foliage should suppress competing vegetation. Thinning is done every two years from the age of 3 years onwards, when the initial spacing is 3 m x 2 m.E. urophylla has good coppicing ability and trees can be expected to produce at least 3 coppice rotations after the initial seedling rotation. The tree is fairly resistant to fire. Yield An annual increment of 20-30 m 3 /ha with bark at 5-10 years of age is usually obtained. Better provenances can yield up to 50 m 3 /ha per year on favourable sites. Hybrids generally yield considerably higher, e.g. a mean annual increment of E. urophylla x E. alba in Congo was 30-35 m 3 /ha, while that of E. urophylla x E. grandis in Brazil

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was 35-70 m'/ha with individual plots yielding over 100 m 3 /ha annually. Mass-propagated cuttings from selected hybrids ofE. urophylla with E. tereticornis J.E. Smith, E. alba and E. grandis in Cameroon gave annual increments of over 30 m 3 /ha in an 8-year rotation. Diseases and pests In conditions of high relative humidity, young seedlings may be susceptible to damping-off. In Indonesia, death of 2-month-old seedlings has been attributed to attack by root fungi such as Botryodiplodia sp., Fusarium sp. and Helminthosporium sp. A canker disease caused by Cryphonectria cubensis is found on E. urophylla in West Africa and South America. Although it is much more resistant than E. grandis or E. saligna J.E. Smith, some provenances are quite susceptible, especially in humid tropical lowland conditions. Seedlings and small trees of E. urophylla are susceptible to termite attack and stem borers such as Zeuzera coffeae and these may also cause damage to older trees. In the Solomon Islands, dieback attributed to the coreid insect Amblypelta cocophaga was observed in 3-4month-old plantings. The introduction of the ant Oecophylla smaragdina and clearing the undergrowth controlled the attack satisfactorily. Genetic resources Since 1963 more than 15 expeditions have collected seed from the natural range of E. urophylla. Much of this material has been used in Indonesian domestic planting programmes, but a significant amount has been established elsewhere. Comprehensive provenance trials exist in Indonesia, Thailand, China, Congo, Ivory Coast, Malawi, Brazil, Colombia, Puerto Rico, and elsewhere. It appears that provenance variation is closely related to the altitudinal gradient of the seed sources. The CSIRO Australian Tree Seed Centre in Canberra holds a comprehensive collection of seed samples of E. urophylla from throughout its natural range. E. urophylla disappeared from the Indonesian island of Solor, but its genetic base is not seriously affected by man as the trees are generally found in rugged and remote areas and are fairly resistant to fire. Breeding An isozyme survey of E. urophylla has revealed a rather unstructured isozyme differentiation pattern with small genetic distances between populations. Only populations from the island of Wetar clustered together on the basis of their isozyme genotypes. This lack of genetic variability between populations contrasts with the high degree of differentiation in morphological characters and growth rates in provenance trials. The main outcome from the provenance trials has

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been the demonstration that provenances from altitudes of above 1500 m perform poorly in the lowland tropics. Moreover, those provenances from lower altitudes (300-1100 m) and from drier locations grow well in humid and sub-humid tropical and subtropical conditions with a dry season of 1-5 months in the coolest part ofthe year. Breeding programmes in Brazil, China, Congo and Indonesia have selected superior individuals in provenance trials and plantations or superior offspring in progeny trials. In Brazil E. urophylla has been hybridized with E. grandis to produce vigorous hybrids for clonal pulpwood plantations. In Cameroon, hybrids with E. tereticornis and E. alba have been used similarly. These hybrids are increasingly being planted following mass vegetative propagation by cuttings. Breeding programmes have focused on optimizing growth rate, stem straightness, wood density and coppicing ability, while rooting capacity of cuttings is an additional prerequisite for mass vegetative production.

field trials in Thailand. In: Boland, D.J. (Editor): Trees for the tropics; growing Australian multipurpose trees and shrubs in developing countries. ACIAR Monograph No 10. Australian Centre for International Agricultural Research, Canberra, Australia, pp. 109-127. I7i Pryor, L.D., Williams, E.R. & Gunn, B.V., 1995. A morphometric analysis of Eucalyptus urophylla and related taxa with descriptions of two new species. Australian Systematic Botany 8: 57-70. I8l Turnbull, J. & Brooker, I., 1978. Timor mountain gum - Eucalyptus urophylla S.T. Blake. Forest Tree Series 214. Commonwealth Scientific and Industrial Research Organization, Melbourne, Australia. 2 pp. 191Umboh, I., Setiawan, I., Kamil, H., Yani, S. & Situmorang, J., 1989. L'application de techniques de culture in vitro à la multiplication d'espèces forestières tropicales en Indonésie [Use of in vitro culture techniques for multiplication of tropical forest tree species in Indonesia]. Bulletin de la Société Botanique de France, Actualités Botaniques 136(3-4): 179-184.

Prospects E. urophylla plays an important role in afforestation in a small but growing number of countries. However, it has the potential to become much more widely used in humid and sub-humid tropical regions, as it belongs to the most productive of the low-latitude eucalypts. Its fast growth, coppicing ability, adaptability to a range of environments, early canopy closure, relative resistance to fire and to diseases and pests, and the various products which can be obtained from the wood, make it a very useful tropical tree. Literature 111 Blake, S.T., 1977. Four new species ofEucalyptus. Austrobaileya 1(1): 1-10. 121 Eldridge, K., Davidson, J., Harwood, C. & van Wijk, G., 1993.Eucalypt domestication and breeding. Clarendon Press, Oxford, United Kingdom, pp. 144-153. 131 Jacobs, M.R., 1981. Eucalypts for planting. 2nd ed. FAO Forestry Series No 11.Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 503-506. I4l Martin, B. & Cossalter, C , 1975. Les eucalyptus des Iles de la Sonde [Eucalypts in the Sunda Islands]. Revue Bois et Forêts des Tropiques 163:3-25; 164: 3-14; 165: 3-20; 166: 3-22; 167: 3-24; 168: 3-17; 169: 3-13. 151 Lamb, D., Johns, R.J., Keating, W.G., IIic, J. &Jongkind, C.C.H., 1993. Eucalyptus L'Hér. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors): Plant Resources of South-East Asia No 5(1): Timber trees: Major commercial timbers. Pudoc Scientific Publishers, Wageningen, the Netherlands, pp. 200-211. 161 Pinyopusarerk, K , 1989. Growth and survival of Australian tree species in

J.W. Turnbull &J.C. Doran

F l e m i n g i a m a c r o p h y l l a (Willd.) M e r r i l l Philip. Journ. Sei. 5: 130 (1910). LEGUMINOSAE - PAPILIONOIDEAE

2n = 22 Synonyms Flemingia congesta Roxb. ex Ait.f. (1812), F. latifolia Benth. (1852), Moghania macrophylla (Willd.) Kuntze (1891). Vernacular n a m e s Indonesia: apa-apa (Javanese), hahapaan (Sundanese), pok-kepokan (Madura). Malaysia: serengan jantan, beringan. Philippines: laclay-guinan (Tagalog), gewawini (Ifugao), malabalatong (Pampanga). Laos: thwàx h'è: h'üad, thwàx h'üad (Vientiane), h'ôm sa:m müang (Xieng Khouang). Thailand: mahae-nok (northern), khamin-nang, khamin-ling (central). Vietnam: t[os]p m[ow] l[as]to, c[aa]y dau ma (Vinh Phu), cai duoi chon (Thuan Hai). Origin and geographic distribution F. macrophylla originated in and is widely distributed in South-East Asia and in India, Sri Lanka, southern China and Taiwan. It has been introduced and naturalized in Papua New Guinea, East, Central and West Africa and is cultivated in tropical America. Uses F. macrophylla is grown in hedges and provides mulch for associated food crops grown in alley-cropping systems, and fuelwood as a valuable by-product. As a green manure it is less effec-

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tive. It is grown on terraces to control soil erosion. In Indonesia, Malaysia, Sri Lanka, West Africa and Madagascar the plant is used as a cover crop and as a shade crop in young plantations of cocoa, coffee, banana and rubber, while in Ivory Coast, it is used in pineapple plantations to reduce nematode infestation and as green manure and mulch. In Costa Rica, it is grown as an understorey in plantations of Honduras pine (Pinus caribaea Morelet var. hondurensis Barrett & Golfari). F. macrophylla is grown as a forage crop and is especially important as a dry season forage e.g. in the savanna zone ofNigeria. It is one ofthe sources of the Arab dye called 'waras' or 'warrus'. 'Waras' is a coarse purple or orange-brown powder, consisting of the glandular hairs rubbed from dry Flemingia fruits, capable of dying silk but not wool or cotton; the active compound is called flemingin. F. macrophylla is a minor host of the Indian and Chinese lac insects. In Indonesia and Malaysia the leaves are used medicinally. Properties The leaves contain per 100 g dry matter: N 2.3-3.8 g, P 0.2-0.25 g, K 1.0-1.4 g, Ca 0.55-0.75 g, and Mg 0.2-0.3 g. The lignin content of the leaves is high, the content of tannic acid fairly low (17.2 g and 2.4 g per 100 g dry matter, respectively). Palatability of the leaves is rather poor and in vitro digestibility (40%) is much lower than that of Leucaena leucocephala (Lamk) de Wit. The leaves decompose slowly, making them more useful as mulch material than as green manure. Under humid tropical conditions, about 50% of an initial quantity of 4 t/ha of dry matter decomposed in 53 days, while in another experiment only 60% of a mulch layer was decomposed after 120 days. The stem contains flavonoid compounds. The weight of 1000 seeds is 15-20 g. Botany Woody, deep-rooting, tussock-forming shrub, 1-4 m tall. Young branches greenish, ribbed, triangular in section, silky. Old stems brown, almost round in section. Leaves digitately trifoliolate; stipules lanceolate, 1-1.5 cm long, covered with silky hairs, early caducous; petiole up to 10 cm long, narrowly channelled, slightly winged; leaflets elliptical-lanceolate, 6-16 cm x 4-7 cm, papery, dark green, base rounded, veins covered with silky hairs, apex rounded to acuminate. Inflorescence a dense axillary raceme, subspiciform, sessile, 2.5-10 cm long, silky; bracts ovate, 3-6 mm long; calyx 6-13 mm long, pale velutinous, green, with 5 lanceolate lobes; corolla with greenish elliptical standard and distinct parallel red veins, wings narrow and much shorter than the keel, light purple at the apex. Pod oblong, inflated,

Flemingia macrophylla (Willd.) Merrill - 1, ering branch; 2,fruiting branch.

flow-

8-15 mm x 5 mm, covered with fine glandular hairs, dehiscent, dark brown, 2-seeded. Seed globular, 2-3 mm in diameter, shiny black. F. macrophylla forms root nodules and fixes atmospheric nitrogen in symbiosis with Bradyrhizobium strains. Root nodules are often difficult to locate, partly because they are very small. Ecology F. macrophylla can be found from sea level up to 2000 m altitude, within a wide range of rainfall patterns, from sub-humid to per-humid (1100-2850 mm/year). It can tolerate fairly long dry spells and is capable of surviving on very poorly drained soils with waterlogging. Its natural habitat is along watercourses, both on clay and lateritic soils, as well as under drier conditions such as in fields infested with Imperata cylindrica (L.) Raeuschel. It tolerates shade and poor, acid soils with a high content ofsoluble aluminium. Agronomy F. macrophylla is propagated by seed. Scarification of the seed is usually required to increase the germination percentage. A good weed-free seed-bed should be prepared, and the necessary fertilizers for a particular soil should be worked in prior to sowing, or banded under the

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row of seed. When planting in a new area, seed should be inoculated with a suitable strain of Bradyrhizobium such as CIAT 4203 or 4215. Planting density varies according to the projected use of the stand. In Indonesia, seed is often sown in rows 90 cm apart with 3-4 seeds planted every 60 cm along the row; in coconut plantations on sloping land, sowing in a dense line along the edges of terraces is recommended. Good weed control is required during the first six months after sowing, since the plants are relatively slow to establish. Once established, they require little attention. The interaction between F. macrophylla hedgerows and associated crops is not fully understood. In an alley cropping experiment in Nigeria, F. macrophylla hedgerows significantly increased the yield of the associated maize crop. This can be attributed only partly to the the effect of mulching or added nutrients: removing the prunings or leaving them on the soil surface caused only small and inconsistent differences in maize yield. However, the combined effect of mulching and added nitrogen fertilizer was very pronounced and stronger than with hedgerows of Senna siamea (Lamk) Irwin & Barneby or Gliricidia septum (Jacq.) Kunth ex Walp. Mulching at a rate of 3 t/ha effectively controls the germination of weed seeds for about 3 months. Under tropical, humid, lowland conditions in the Ivory Coast, with 10 000 plants/ha and 9 regrowth cycles of 3 months each, an average annual production of 12 t/ha of leaf dry matter has been achieved, although typical yields in South-East Asia may be closer to 8 t/ha. Plants can be cut more frequently than every 3 months, but preferably not at intervals of less than 40 days. They will survive under this cutting regime for many years. Insect pests such as the fly Agromyza sp. reduce seed production by laying eggs in green pods. In Malaysia, spraying with Endrex (1:800) once every two weeks after flowering has begun gives effective control. Genetic resources and breeding Germplasm collections are maintained at the Centro International de Agricultura Tropical (CIAT, Cali, Colombia), the Research Institute for Animal Production (Ciawi, Bogor, Indonesia), Australian Tropical Forage Genetic Resource Centre (ATFGRC, CSIRO, Canberra, Australia), and the International Plant Genetic Resources Institute (IPGRI, Bangkok, Thailand). Prospects F. macrophylla has excellent coppic-

ing capacity and is promising when used in hedges to provide mulch to associated food crops in alley cropping and forage. As a green manure and feed F. macrophylla is inferior to species such as Leucaena leucocephala and Gliricidia sepium, since its leaves decompose slowly and are less easily digested. Owing to its slow decomposition, the mulch has long-term effects in weed control, moisture conservation and reduction of soil temperature. Furthermore, F. macrophylla is useful as a cover crop in perennial plantations, as a shelter belt in erosion control, and in planted fallows for soil improvement. Improvement ofthe crop's early development and its integration into alley-cropping systems and planted fallows deserve priority in research. Literature 111Asare, E.O., 1985. Effect of frequency and height of defoliation on forage yield and crude protein content of Flemingia macrophylla (flemingia). In: Proceedings of the XV International Grasslands Congress, August 24-31, 1985, Kyoto, Japan. Science Council of Japan and Japanese Society of Grassland Science, Nishihasuno, Japan, pp. 164-165. I2l Budelman, A., 1988. Leaf dry matter productivity of three selected perennial leguminous species in humid tropical Ivory Coast. Agroforestry Systems 7: 47-62. I3l Budelman, A., 1991. Woody species in auxiliary roles: live stakes in yam cultivation. Royal Tropical Institute, Amsterdam, the Netherlands. 151 pp. I4l Bourgoing, R., 1990. Choice of cover crop and planting method for hybrid coconut growing on smallholdings. Oléagineux 45: 27-28. I5l Gutteridge, R.C., 1994. Other species of multipurpose forage. In: Gutteridge, R.C. & Shelton, H.M. (Editors): Forage tree legumes in tropical agriculture. CAB International, Wallingford, United Kingdom, pp. 97-118. 161 Kachaka, S., Vanlauwe, B. & Merckx, R., 1993. Decomposition and nitrogen mineralization of prunings of different quality. In: Mulongoy, K. & Merckx, R. (Editors): Soil organic matter dynamics and sustainability of tropical agriculture. Proceedings of an International Symposium held in Leuven, Belgium, 4-6 November 1991. John Willey, Chichester, United Kingdom, pp. 199-208. 171 Rubber Research Institute of Malaysia, 1975. Species and varieties of Flemingia in Malaya. Planters Bulletin 61: 78-85. I8l SchultzeKraft, R., 1985. Development of an international collection of tropical germplasm for acid soils. In: Proceedings of the XV International Grasslands Congress, August 24-31, Kyoto, Japan. Science Council of Japan and Japanese Society of Grassland Science, Nishihasuno, Japan, pp. 1-3. I9l

GLIRICIDIA

Skerman, P.J., Cameron, D.O. & Riveros, F., 1988. Tropical forage legumes. 2nd Edition. FAO Plant Production and Plant Protection Series No 2. Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 561-562. A. Budelman &M.E. Siregar

Gliricidia s e p i u m (Jacq.) K u n t h e x Walp. Repertorium bot. syst. 1:679 (1842). LEGUMINOSAE - PAPILIONOIDEAE

2re=20 Synonyms Gliricidia maculata (Kunth) Kunth ex Walp. (1842). Vernacular n a m e s Gliricidia, mother of cocoa, Mexican lilac (En). Quickstick (Am). Indonesia: gamal, liriksidia (Javanese). Malaysia: bunga jepun (also used for Thevetia spp.). Philippines: kakawate (general), madre-cacao, balok-balok (Tagalog). Laos: kh'è: no:yz, kh'è: fàlangx. Thailand: khae-farang. Vietnam: anh d[af]o g[is]a, s[as]t thu, h[oo]ng mai. Origin and geographic distribution Gliricidia is a native ofthe seasonally dry Pacific Coast of Central America. It has long been cultivated and is naturalized in tropical Mexico, Central America and northern South America. It was also introduced to the Caribbean and later to West Africa. The Spaniards took it to the Philippines in the early 1600s. From Trinidad it was taken to Sri Lanka in the 18th Century; from there it reached other Asian countries including Indonesia (about 1900), Malaysia, Thailand and India. Uses Gliricidia is considered to be the most widely cultivated multipurpose tree after leucaena (Leucaena leucocephala (Lamk) de Wit). In former times it was mainly used as a shade tree in plantation crops, but more recently it has become a widely cultivated multipurpose tree integrated into several cropping systems, e.g. as a shade tree in tea, cocoa or coffee plantations, as live stakes to support black pepper, vanilla and yam (in West Africa), as a hedge and green manure crop in intercropping systems such as alley-cropping systems. It has also been planted to stabilize soil, to prevent erosion and to reclaim denuded land or land infested with Imperata cylindrica (L.) Raeuschel. In this last respect gliricidia has been found to be more effective than leucaena. The wood is often utilized as firewood, for charcoal production or as posts and farm implements, and locally for furniture, construction and railway

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sleepers. Gliricidia provides useful forage in the form of leaves, green stem and bark, and is commonly used to supplement poor quality, low protein roughage, especially in dry seasons when it may become a major source of feed for goats and cattle in dryland cropping areas. Its forage has been reported to be toxic to horses, but clear confirmation is lacking. Leaf meal can also be fed to poultry and rabbits. Flowers are a source of nectar for bees. Seeds, bark, leaves and roots may be used as a rodenticide and pesticide after fermentation. Gliricidia is often planted as an ornamental. The juice of the leaves, bark and roots is used as a traditional anti-dermatophyte to control eczema and to alleviate itches and wounds. Properties Gliricidia prunings have a low C/N ratio, a low content of lignins, silica and polyphenols, and a high nutrient level. When applied as green manure they quickly decompose; in one trial gliricidia residues had a half-life of20 days, which is shorter than that of other green manure crops such as Leucaena leucocephala or Flemingia macrophylla (Willd.) Merr. Consequently, gliricidia mulch has only a short-lived effect on soil temperature and moisture content. Analyses of gliricidia prunings (leaves and twigs) grown on an alfisol in Nigeria indicated a nutrient content per 100 g dry matter of: N 3.1-3.6 g, P 0.13-0.20 g, K 2.6-2.7 g, Ca 1.2-1.6 g, Mg 0.3-0.45 g, lignin 11.6 g, cellulose 19.4 g, hemicellulose 12.2 g, polyphenols 1.6 g and a C/N ratio of about 13. Water extracts of both fresh and dried gliricidia leaves have been found to produce some allelopathic effect caused by phenolic acids. The effect does not last long and can be eliminated by applying gliricidia mulch at least one week before planting. Forage quality varies with age, plant part, season and genotype. It is highest in the youngest leaves; with maturity N concentrations decrease slightly and crude fibre increases. The leaves contain 3-5% N, 13-30% crude fibre and 6-10% ash. Digestibility ranges from 48-77%. In 3-month-old growth, gliricidia bark had lower N concentrations than the leaves, but higher levels than the stem. Palatability is problematical, as the forage contains some anti-nutritional factors, with 1-3.5% flavonol and 3-5% total phenols on a dry matter basis. Ruminants unaccustomed to eat the foliage may initially refuse it. However, once they have overcome their initial aversion they will eat a high proportion in their diet for extended periods of time. In some cases it has been observed that oneday-old wilted leaves are preferred to fresh leaves; also silage is more palatable than fresh foliage.

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Gliricidia has light-brown sapwood and darkbrown heartwood turning reddish on exposure to air. It is hard, coarse-textured with irregular grain, very durable and termite-resistant. The wood has a high density of up to 750 kg/m 3 and proves difficult to work. The wood of young coppices is less dense, about 500 kg/m3. As the bole seldom has a diameter of more than 40 cm and a length of 8 m, especially in coppiced trees, timber oflarge dimensions israre. Theheartwood ofgliricidia burns slowly thus producing good embers, and gives offlittle smoke or sparks; its energy value is 19800-20 600 kJ/kg. The weight of 1000 seeds is about 125 g. Description A small deciduous tree up to 12m tall with a short trunk up to 50 cm in diameter, with smooth or slightly fissured, whitish-grey to light brown bark, often branching from the base; the mature tree has an irregular spreading crown of thin foliage. Leaves alternate, pinnate, 15-40 cm long; petiole 5mm long; rachis slender, yellowgreen, finely hairy; leaflets 7-17 per leaf, opposite except in upper part ofrachis, elliptical or lanceo-

Gliricidia sepium (Jacq.) Kunth ex Walp. - 1,leaf; 2, flowering branch; 3,fruiting branch.

late, 3-6 cm x 1.5-3 cm, rounded or cuneate at base, acuminate at top, thin, dull green and glabrous above, grey-green and often pubescent beneath. Flowers in a 5-12 cm long, axillary raceme, about 2 cm long, on an 8-12 mm long, slender pedicel; calyx campanulate, 5-toothed, light green tinged with red; corolla whitish-pink or purple, with a broad standard, folded back and yellowish near the base, 2 oblong, curved wings, and a narrow keel; stamens 10,white, 9 united in a tube and 1free; pistil with stalked, narrow, red ovary and whitish, curved style. Pod narrow, flat, 10-15 cm x 1.2-1.5 cm,yellow-green when immature, turning yellowish-brown, shortly stalked and with a short mucro, splitting open at maturity, 4-10-seeded. Seed ellipsoid, about 10mm long, shiny, dark reddish-brown. Growth and development Seeds germinate in 3-10 days. Early seedling growth is slow, but once established, growth is fast and the annual increase in height maybe as much as 3 m. The root system is relatively weakly developed and does not extend strongly laterally. Flowering may start at the age of 6-8 months; abundant flowering takes place during the dry season if the tree has not been coppiced or pruned, after it has shed its leaves. Flowers are insect-pollinated; a wide variety ofinsects, often large bees, are attracted tothe abundant nectar. These may distribute pollen over several kilometres. Pods ripen 40-55 days after flowering, the seeds are mature when the pods turn yellow-brown. Fruiting is relatively uniform, with about 20 days from first to last seed dehiscence. Inits native area seed production is usually abundant and can be predictably timed. In more humid areas, shoot growth tends tobe continuous and the evergreen tree flowers only sporadically on the basal parts of twigs from which the leaves have fallen. Other botanical information G. maculata has been used extensively as a synonym for G. sepium. G. maculata has been recently proposed as a distinct species with a different natural geographical distribution, i.e. Yucatan Peninsula, northern Guatemala and Belize. It differs from G. sepium in having white flowers and smaller pods and seeds. Most gliricidia planted as exotics can be attributed to G. sepium, but former introductions ofG.maculata cannot beruled out. Ecology In its native range the climate is relatively uniformly sub-humid with an annual rainfall of 900-1500 mm and a five-month dry period. Gliricidia has been introduced successfully in more humid zones with up to 3500 mm annual

GLIRICIDIA

rainfall and without a marked dry season. In its native range the mean annual temperature varies from 20-29°C, the mean maximum temperature of the hottest month from 34-41°C, the mean minimum temperature of the coldest month from 14-20°C. Light night frost is tolerated, but not prolonged frost. Gliricidia occurs naturally in early and middle successional vegetation types on disturbed sites such as coastal sand dunes, river banks, floodplains and fallow land, from sea level up to 1500 m altitude. It can tolerate a wide range of soil types, both alkaline and acidic, but prefers free drainage. It is also more tolerant of acid and low fertile soils than leucaena, but will respond to fertilizer application on such soils. It is not as well adapted to the subtropics as leucaena; leaves are shed with the onset of lower temperatures during winter, and plants are less resistant to frost. It is, however, more tolerant of waterlogged conditions than leucaena. In its native, seasonally dry habitat, trees are often exposed to annual fires. Gliricidia tolerates such fires well and trees quickly resprout when the rains start, which explains the abundance of the tree in secondary vegetations and fallows. Propagation and planting Gliricidia can be propagated easily by seed and cuttings. Direct seeding is seldom used, and potted plants or barerooted stock are raised in nurseries. Fresh seed or seed that has been preserved in cold storage has a germination percentage of 80-90%. Seed may be sown directly in nursery beds or in polythene bags. Seed pretreatment is not necessary. Nursery stock can be transplanted after 10-12 weeks. Vegetative propagation is by large cuttings, 3-6 cm thick and 0.5-2 m long; the bark may be incised to promote rooting. Cuttings should be taken from mature branches with brownish-green bark and planted fresh. Rooting starts 6-7 weeks after planting. Plants grown from cuttings may have 50-150 root nodules after 3 months, compared with 20-70 nodules after 6 months on plants from seed. Trees obtained from cuttings have shallower roots than trees grown from seed. Inoculation with an appropriate strain ofBradyrhizobium and fertilization can stimulate growth on degraded lands. On soils with low P content gliricidia is mycorrhiza-dependent; inoculation with ectomycorrhizal fungi (Boletus suillus) or vesicular-arbuscular mycorrhizal fungi (VAM) may enhance plant growth. Gliricidia may be planted in hedges spaced 4-10 m apart with 25-100 cm between trees in the rows, or as live fences with 10-25 cm spacing.

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When it is used for live posts for black pepper or vanilla the crops can be planted at the same time as the tree. In fodder plots spacings of 0.25 m x 1.0 m or wider may be used; yields of leaves are little affected by planting densities ranging from 5000-40 000 trees/ha. Sometimes, trees are planted at wider spacings (e.g. 10 m x 10 m) over pasture lands. Where animals are grazed in young plantations, young trees must be protected. In woodlots spacings of 1.5-2 m x 2-2.5 m are common. Husbandry Gliricidia can be managed for either wood or foliage (green manure, fodder) production, for shade, fencing or for live posts. It may be planted in pure stands for the production of fuelwood, as protein banks which are periodically harvested for fodder, or for land reclamation. Hedges may be planted around homesteads, in pastures and along the contours in fields to serve as erosion barriers and be managed for green manure production. Sometimes some of the tree prunings obtained from the alley-cropping system are fed to animals. Experimental data indicate that at low crop yields and low crop response to mulching, feeding part of the tree foliage to small ruminants is economically gainful. Gliricidia hedgerows for fodder production may also be established in existing pastures and interplanted with pasture grasses. In Sri Lanka the tree has been integrated in pastures under coconut to produce dry season fodder. In Bali, Indonesia, gliricidia has been incorporated in a 'Three Strata Forage System' consisting of a strip of 5 m wide, in which fodder trees (Ficus subcordata Blume, Lannea coromandelica (Houtt.) Merrill, Hibiscus tiliaceus L.), shrub legumes (Gliricidia sepium, Leucaena leucocephala, Acacia glauca (L.) Moench) and grasses and herbaceous legumes (Cenchrus ciliaris L., Panicum maximum Jacq., Stylosanthes spp.) are combined. Cattle feed mainly on the grass-legume stratum in the wet season, the shrub legumes in the mid-dry season and leaves from the fodder trees in the late dry season. A wide variety of agricultural crops or fodder grasses and legumes can be grown together with gliricidia. Although the competitive effect of the tree on crop and pasture grass production depends on the species, site conditions and management it seems to be limited. Due to its open crown and thin foliage and weakly developed root system the tree does not provide heavy competition. In alleycropping experiments it was found that crop growth next to the hedges is depressed less by gliricidia than by alternative hedge species such as

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Erythrina poeppigiana (Walpers) O.F. Cook. Similarly, when used as living posts for yam cultivation, tuber yields were higher with gliricidia than with leucaena. In pastures, gliricidia may be combined with Panicum maximum. Jacq. var. trichoglume Robijns, Cenchrus ciliaris, Urochloa mosambicensis (Hack.) Dandy, Stylosanthes seabra Vogel, and Stylosanthes hamata (L.) Taub. Even if grass production is depressed, gliricidia production may compensate for this loss, because the total production is more evenly distributed over the year. Gliricidia has improved the survival of ewes and lambs, lambing percentage, and birth weight and growth of lambs when fed as a supplement to poor quality grass. It is normally recommended that gliricidia be used mixed with either grass, straw or other roughages. When fed to poultry in place of lucerne (Medicago sativa L.), levels not exceeding 2-4% are recommended. Diseases and pests Few serious diseases and pests have been recorded. Some problems with foliar diseases caused by Pellicularia filamentosa (India) and Colletotrichum gloeosporioides and Cercosporidium gliricidiasis (Nigeria) have been noted; in Trinidad a root fungus attacks the tree, but not very seriously. In the Caribbean a number of insects, such as aphids, mealy bugs and scale insects attack the tree. One of the reasons for the popularity ofgliricidia is its complete resistance to the leucaena psyllid (Heteropsylla cubana), which seriously attacks many cultivars of Leucaena leucocephala. When intercropped the tree may affect crop pests positively or negatively. In several cases the tree has been reported to control pests, e.g. termite damage to tea was minimized in Sri Lanka, as was stem-borer damage to rice in the Philippines. In India on the other hand, it was found to increase the number of aphids (Aphis craccivora) causing rosette disease in groundnut; in Indonesia, this aphid adversely affected buffelgrass (Cenchrus ciliaris) intercropped with gliricidia. Harvesting The first harvest ofgliricidia can be as early as 6-8 months from plants grown from cuttings and 12-16 months from plants grown from seedlings. There should be only one or two harvests per year during the first 2 years. Harvesting should be less intensive (every 3-4 months) in the dry season than during the rainy season (every 2-3 months). Regrowth should be 1-2 m in height before each harvest. To obtain fodder during the dry season the trees should be cut about 3months before the onset ofthis season. If trees are not cut 4-6 months before the dry sea-

son they will shed their leaves during the dry season. Cutting heights commonly range from 0.5-2 m. Trees grown along contours and in fodder banks are usually cut lower than those cultivated in living fences or as shade trees in pastures, where browsing cattle may interfere with regrowth. Forage from gliricidia is usually cut by hand and left on the ground for grazing or carried to paddocks or livestock sheds. Acceptable silage can be prepared using standard techniques; the chopped forage may be mixed with grasses or maize and additives such as molasses and sugar cane or formic acid (0.85%) should be added to provide fermentable carbohydrate. In woodlots the first harvest can be carried out after 3-4 years, giving wood yields of 8-15 m 3 /ha. From then on, coppicing is done every 2-3 years yielding up to 40%more than the first harvest. Yield Under average conditions yields of 3-4 kg dry matter per tree per harvest may be obtained. In Nigeria gliricidia hedgerows interplanted with 4 rows ofPanicum grasses yielded 20 t/ha per year ofmixed dry matter, which was sufficient to feed 3 head of cattle. Annual yields of 9-16 t/ha of leaf dry matter or up to 43 t/ha fresh leaves have been obtained in fodder plots. In woodlots coppiced every 2-3 years the wood yield varies from 10-20 m 3 /ha. Wood production in living fences has been reported at 9 m 3 /km per year. Harvested produce is usually used locally. Marked differences in yield have been found between different provenances (e.g. up to 500% for biomass production). Genetic resources Major germplasm collections are being maintained at the Oxford Forestry Institute in the United Kingdom, the Centro Agronómico Tropical de Investigation y Ensenanza (CATIE, Turrialba, Costa Rica), and at the Humid Zone Programme of the International Livestock Research Institute (ILRI, Ibadan, Nigeria). In Asia, collections have been made by the Visayas State College of Agriculture (VISCA, Leyte, the Philippines). The Oxford Forestry Institute administers an international network of provenance evaluation involving 29 provenances from 8 Latin American countries. CATIE collected 49 provenances from Costa Rica; the ILRI Humid Zone Programme has developed a high yield bulk composite from four Costa Rican accessions. Breeding Early germplasm introductions in many countries usually had a very narrow genetic base and distinct types have evolved in several areas. They are largely arboreal types selected for

GREVILLEA

use as shade trees, and may not be optimally suited for other uses. Provenance evaluations indicate significant differences in growth rate; local landraces in Indonesia, Nigeria, the Philippines and Sri Lanka have been outperformed by new introductions. At some sites large differences in biomass production were found, with some provenances showing superior production of leaves and wood, others with outstanding leaf production but poor wood production. This indicates the need for distinct selection programmes for high-yielding, palatable fodder cultivars, for arboreal cultivars for wood production, or for cultivars combining wood and foliage production. Recently, progeny testing with some superior provenances has started as a basis for future seed orchard establishment. Rapid genetic gains can be expected, as seed production starts early, superior types can be cloned and production cycles are short. Prospects G. sepium is an extremely versatile multipurpose tree well adapted to a wide range of humid and sub-humid areas and soil conditions, including acid and infertile soils. Favourable properties include its versatility and ease of incorporation in a variety of agricultural production systems. It can be grown together with arable crops in alley-cropping systems, with fodder crops such as grasses or small legumes, or as shade trees in perennial crops. Its auxiliary effect on other crops is facilitated by its relatively open crown and nonspreading root system causing little competition. Plant residues of gliricidia have a relatively high nutrient level and decompose quickly thus having a high direct nutritional contribution to crops but a low mulching effect. It is also showing considerable promise as a fodder crop throughout the tropics, although the quality (anti-nutritional factors) of its forage is still being debated. Although most fodder is produced in the wet season, the tree can be managed to provide fresh leaf during the dry season. Its prospects may be further enhanced by breeding programmes to improve production and forage quality and the development of innovative production systems such as the 'Three Strata Forage System'. It has excellent properties for site reclamation, including suppression of obnoxious weeds such as Imperata cylindrica (L.) Raeuschel. Literature 111Anoka, U.A., Akobundo, I.O. & Okonkwo, S.N.C., 1991. Effects of Gliricidia sepium (Jacq.) Steud. and Leucaena leucocephala (Lam.) De Wit on growth and development of Imperata cylindrica (L.) Raeuschel. Agroforestry Systems 16: 1-12. I2l Budelman, A., 1990. Woody legumes as live support systems in yam cultiva-

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tion. I. The tree-crop interface. II. The yam - Gliricidia sepium association. Agroforestry Systems 10: 47-59, 61-69. 131 Ezenwa, I., Reynolds, L., Aken'ova, M.E., Atta-Krah, A.N. &Cobbina, J., 1995. Cutting management of alley cropped leucaena/gliricidia-Guinea grass mixtures for forage production in southwestern Nigeria. Agroforestry Systems 29: 9-20. 141Glover, N., 1989. Gliricidia production and use. Nitrogen Fixing Tree Association, Waimanalo, Hawaii, United States. 44 pp. I5l Jabbar, M.A., Cobbina, J. & Reynolds, L., 1992. Optimum fodder-mulch allocation of tree foliage under alley farming in southwest Nigeria. Agroforestry Systems 20: 187-198. I6l Lehmann, J., Schroth, G. & Zech, W., 1995. Decomposition and nutrient release from leaves, twigs and roots of three alley-cropped tree legumes in central Togo. Agroforestry Systems 29: 21-36. 171 Rao, M.R., Muraya, P. & Huxley, P.A., 1993. Observations of some tree root systems in agroforestry intercrop situations, and their graphical representation. Experimental Agriculture 29: 183-194. I8l Simons, A.J. & Stewart, J.L., 1994. Gliricidia sepium - a multipurpose forage tree legume. In: Gutteridge, R.C. & Shelton, H.M. (Editors): Forage tree legumes in tropical agriculture. CAB International, Wallingford, United Kingdom, pp. 30-48. 191 Tian, G. & Kang, B.T., 1994. Evaluation of phytotoxic effects of Gliricidia sepium (Jacq.) Walp. prunings on maize and cowpea seedlings. Agroforestry Systems 26: 249-254. llOl Withington, D., Glover, N. & Brewbaker, J., 1987. Gliricidia sepium (Jacq.) Walp.: management and improvement. Nitrogen Fixing Tree Association Special Publication 87-01. Waimanalo, Hawaii, United States. 255 pp. K.F. Wiersum &I.M. Nitis

G r e v i l l e a r o b u s t a A. C u n n . e x R. B r . Suppl. prodr. fl. Nov. Holl.: 24 (1830). PROTEACEAE

2n =20 Vernacular n a m e s Silky oak, silver oak (En). Silk oak (Am). Indonesia: salamandar (Sundanese). Thailand: son-india (central). Vietnam: ng[aa]n hoa (northern), tr[ax]i ban (southern). Origin and geographic distribution G. robusta occurs naturally in Australia, over the latitudinal range of 26-30°S in southern Queensland and northern New South Wales from the coast up to 160 km inland. It has been introduced into warm temperate, subtropical and tropical high-

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AUXILIARY PLANTS

land regions around the world and is widely planted in India, Sri Lanka and many countries in Africa. It performs poorly in lowland tropical environments and is not grown very commonly in Malesia. Uses G. robusta is used to provide high shade for tea and coffee plantations in southern Asia and Africa. It is now very popular in agroforestry systems in the highlands of east and central Africa, being planted in rows along farm boundaries and between fields, and scattered among crops. It is regarded as more compatible with crops on small farms than most other tree species. In Burma (Myanmar), it is planted on a limited scale as a shade tree in coffee plantations. The wood is used for firewood, poles and sawn timber. The leaves are applied as mulch. Some farmers in Kenya use fresh leaves as a dry-season fodder supplement for cattle. G. robusta has some value for honey production. It is planted in many countries, e.g. in Thailand, for shade and ornamental purposes because of its attractive fern-like foliage and brilliant orange floral display. The cut leaves are used in flower arrangements and young plants are grown as indoor pot plants in Europe. Properties Leaves contain rutin, a quercetin glucoside (about 0.6 g per 100 g dry matter). Through contact with the leaves sensitive persons may develop contact dermatitis due to tridecylresorcinol, a chemical compound related to the allergen of Toxicodendron spp. (Anacardiaceae). Gum from G. robusta exudates contains small amounts ofhydroxyproline, a free amino acid, in addition to galactose and arabinose. The flower buds, fruits and seeds are cyanogenic. Seed extracts exhibit antifungal activity. The weight of 1000 seeds is 10-20 g. The air-dry density of the heartwood is 550-600 kg/m 3 , that of sapwood and branches is lower. The sapwood is cream-coloured, heartwood pale pink or red-brown after drying. Broad rays give the wood an attractive appearance on both the quartersawn and backsawn faces. The sawn timber is of medium strength and is used for furniture, flooring, packing cases, and the manufacture of small wooden items. The wood is used for firewood in African countries, and trials indicate it is suitable for pulping. Mean fibre length is about 1.5 mm and width about 26 p.m. Some fair-skinned people are allergic to the sawdust. Description An erect, single-stemmed tree up to 25(-40) m tall with a stem diameter of 50 cm or more and with a strong taproot. Crown conical and symmetrical with major branches spaced at

Grevillea robusta A. Cunn. ex R. Br. - 1, habit; 2, leaf;3, inflorescence; 4, young flower with stigma retained in bud; 5, tepal with anthers directly attached; 6, mature flower with extended style and stigma; 7,fruits; 8, winged seed. intervals of about 1m, projecting upwards at a 45° angle. Bark dark greyish-brown, rugged, furrowed. Branchlets angular and ridged, subsericeous to tomentose, becoming glabrous on older growth. Leaves pinnate with (4-)10-20 pinnatifid segments, fern-like; petiole 1.5-6.5 cm long; blade in outline 10-34 cm x 9-15 cm, secondary lobes or segments entire or again lobed, lanceolate or rarely linear, terminal one mostly longer than 2.5 cm, margins recurved, upper surface glabrous, green, lower surface subsericeous, silvery. Inflorescence a raceme, 7-12 cm long, simple to 4branched from near the base, borne on very short, leafless, tomentulose branches on the older wood, many-flowered and all flowers pointing one way; rachis slender to stoutish, glabrous; pedicel 1.5 cm long, glabrous; flowers borne in pairs, 2 cm long, bright orange to golden-yellow or golden-brown; tepals 4, glabrous inside and outside, tube 0.6-1 cm long, rolled back under the 3 mm long ovate

GREVILLEA

limb, with concave apex of each tepal holding a small anther 0.1 cm long; receptacle slightly oblique with prominent disc; ovary glabrous, stipitate; style filiform, 1.5 cm long, protruding from a slit on the lower side of the perianth tube before the apex is free from the limb, accrescent during and after anthesis, ultimately straight and erect, bearing the small stigma at its apex. Fruit a 2seeded follicle, broad, very oblique, boat-shaped, pointed, 1.5-2 cm long with a slender persistent style. Seed flat-ovoid, 13-19 mm x 8-10 mm x 0.8-0.9 mm, brown, with papery wing all around. Growth and development Seed germinates readily in a moist environment. The optimum temperature for germination is about 25°C. Seedling growth is quickest during the summer months at temperate latitudes, and during the wet season in tropical highlands. In its natural range G. robusta is semi-deciduous, shedding most of its leaves in the dry spring. Substantial leaf fall is also noted in the dry season in tropical environments. When climate and soil are suitable and weed competition not severe, annual height and diameter increments of at least 2 m and 2 cm respectively are usually achieved for the first few years in row plantings on farms. Annual height increments of 3 m have been observed at the most favourable sites. The tree first flowers when about 6 years old. In the region of natural occurrence, flowering occurs over a few weeks in October-November, but when planted in equatorial latitudes, flowering is sporadic throughout the year, or absent as in Jakarta. During flower development the style protrudes through a slit in the lower side of the perianth tube before the perianth apex opens, giving the flower a 'looped' appearance. At anthesis, the apex of the perianth opens and the perianth falls away, depositing pollen on the stigma. Studies in Australia show that at the time of pollen deposition the receptive cells of the stigma are still covered by protective cells. The stigma does not become sticky and receptive until several days after anthesis, by which time the pollen has usually fallen off. Birds attracted by the nectar produced by the scales around the gynophore are believed to be the principal pollinating agents. The period from fertilization to fruit maturity is about 2 months. Fruits open during hot, dry weather, releasing the seeds, which can be carried considerable distances by wind. Seeds exhibit no dormancy, and remain viable for at least two years if dried to below 8% moisture content and stored dry and cool (20°C or less).

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Proteoid roots develop seasonally near the growing tips of the young roots; these regions with a cylindrical mass of finely-divided root hairs are believed to increase the plant's ability to take up water and nutrients under unfavourable conditions. Ecology G. robusta occurs naturally in two distinct habitats. It grows in riverine rain forest of the Castanospermum australe A. Cunn. & C. Fraser ex Hook, association, usually within a few dozen metres of the water's edge on soils of fairly high fertility and good moisture availability. It also occurs away from the rain forest along creeks and rivers in association with Casuarina cunninghamiana Miquel. The second major habitat is the vine forest dominated byAraucaria cunninghamii Aiton ex D. Don, which covers extensive areas including steep upper-valley slopes. This type of forest is found on basalt-derived soil. G. robusta occurs at very low densities in these forests. Climatic studies in the areas of natural and planted occurrence indicate the following ecological requirements for satisfactory growth: mean maximum temperature of hottest month 25-31°C, mean minimum temperature of coldest month 2-12°C, mean annual temperature 14-23°C, mean annual rainfall 700-1700 mm, dry season 0-6 months (0-4 months on shallow soils or towards the hotter extreme of the acceptable temperature range). Rainfall distribution has a summer maximum in the region of natural occurrence, but G. robusta also grows well in climates with a winter maximum or a bimodal rainfall distribution. Growth is best over the altitudinal range of 130-2300 m at equatorial latitudes, the preferred altitudinal range decreasing to 0-1000 m at 30° latitude. In temperate areas G. robusta can survive moderate winter frosts. It is not resistant to persistent strong winds. Soils should be of moderate to high fertility with pH of 4.5-8; heavy clays and waterlogging are not tolerated. On acid soils, symptoms of boron deficiency and manganese toxicity have been observed. Propagation and planting G. robusta can be propagated by seed and by cuttings. No pretreatment of seed is required for germination. Seeds are usually germinated on loamy soil with a thin covering of sand. Seedlings are pricked out when their second leaf pair starts to develop and are put into tubes containing a fertile loamy potting mix. Seedlings are grown in the nursery until planting out during the rainy season when a height of 20-40 cm is attained. Farmers also obtain plant-

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ing stock by digging up Wildlings. Cuttings can easily be established using shoots from seedlings or saplings, which can also be air layered. A plant density of 800-1200 trees per ha is recommended for plantations. Husbandry Some control of competing vegetation is required for the first 1-2 years after planting. This is normally achieved by manual weeding. Fertilizer is seldom applied; 50 g per tree of an NPK fertilizer (12:12:12) applied shortly after planting would be appropriate for infertile soils. If symptoms of boron deficiency such as dieback of main leader, bronze leaf colour and loss of leaves become apparent, an application of about 100 g of borax per tree at planting or preferably the equivalent amount of the less soluble ulexite is recommended. G. robusta regrows well after complete defoliation following pruning and pollarding, which can be carried out repeatedly to yield wood and to regulate shading and competition with adjacent crops. Diseases and pests In the lowland humid tropics and other very humid regions G. robusta is vulnerable to attack by fungal diseases such as Corticium salmonicolor. Fungi such as Amphichaeta grevilleae, Cercospora sp. and Phyllostica sp. have been observed to cause considerable damage to leaves and stems of young plants in Sri Lanka, particularly if they are overwatered in the nursery. Under lowland conditions in the Caribbean G. robusta is severely attacked by the scale insect Asterolecanium pustulans. Attack by termites can be a problem when it is planted on dry sites in Africa. In Peninsular Malaysia the big white ant Termes gestroi destroyed experimental trees. Harvesting Farmers in the East African highlands commonly harvest branches ofG.robusta by high pruning and pollarding every 3-4 years from 4-6 years after planting onwards, using the leaves for mulching or sometimes as cattle fodder. The main trunk of the tree may be harvested as a sawlog from the age of 15-25 years. Yield When grown in monoculture in woodlots or plantations, annual wood increments of 10-15 m 3 /ha of G. robusta as measured over bark with stem diameter down to 10 cm have been recorded in rotations of 10-20 years in Uganda, Kenya and Hawaii. Handling after harvest Firewood of G. robusta dries quickly, within a few days of cutting, except in wet weather. Logs are commonly pit-sawn green in rural areas. Timber for external use has to be treated chemically to improve its dura-

bility. It is susceptible to attack byLyctus borers. Genetic resources Isozyme studies have demonstrated that the genetic base of G.robusta in a number of African countries is very narrow. In recent years the Australian Tree Seed Centre of the Commonwealth Scientific and Industrial Research Organization (CSIRO) and the Queensland Forest Service have distributed seed collections from natural provenances, covering the altitudinal and geographical range of sites where it occurs, for evaluation in other countries. Breeding Studies of reproductive biology and genetic improvement programmes have commenced in several African countries, coordinated by the International Centre for Research in Agroforestry (ICRAF). Several provenance and progeny trials have been established in Africa and India, and selection of preferred genotypes has commenced in Kenya. Prospects Because of the importance of G. robusta in the tropical highlands ofAfrica, considerable research effort has started in the fields of genetic improvement and silviculture for agroforestry. G. robusta is little used in South-East Asia, but could be of substantial value as an agroforestry tree for use on small farms in the highlands of countries such as Burma (Myanmar), Indonesia, Laos,the Philippines and Vietnam. Literature 111 Brough, P., 1933.The life history of Grevillea robusta Cunn. Proceedings ofthe Linnean Society of New South Wales 58: 33-73. 121 Harwood, C.E., 1989. Grevillea robusta: an annotated bibliography. International Council for Research in Agroforestry (ICRAF), Nairobi, Kenya. 123 pp. 131 Harwood, C E . (Editor), 1992. Grevillea robusta in agroforestry and forestry: proceedings of an international workshop. International Council for Research in Agroforestry (ICRAF), Nairobi, Kenya. 190 pp. 141 Kalinganire, A., Harwood, C.E., Simons, A.J., Moncur, M.W. & Slee, M.U., 1996. Reproductive ecology of Grevillea robusta in western Kenya. In: Dieters, M.J., Matheson, A.C., Nikles, D.G., Harwood, C E . &Walker, S.M. (Editors): Tree improvement for sustainable tropical forestry. Proceedings of the QFRI-IUFRO Conference, Caloundra, Queensland 27 October-1 November 1996. pp. 238-243. I5l McGillivray, D.M. & Malinson, R.O., 1993.Grevillea, Proteaceae, a taxonomie revision. Melbourne University Press, Melbourne, Australia. 465 pp. 161 Skeney, K.R., Sprent, J.L. & Ong, CK., 1996. Cluster roots of Grevillea robusta - foragers or scavengers? Agroforestry Today 8: 11-12. 171 Sleumer, H., 1955. Proteaceae. In: van Steenis, C.G.G.J. (Editor): Flo-

HOMONOIA

ra Malesiana, Series 1, Vol. 5. Noordhoff-Kolff, Djakarta, Indonesia, pp. 154-157. C E . Harwood

H o m o n o i a riparia Lour. Flora Cochinch.: 637 (1790). EUPHORBIACEAE

2n =42 (44) Synonyms Adelia neriifolia Heyne ex Roth (1821), Lumanaja fluviatilis Blanco (1837), Ricinus saücinus Hassk. (1844). Vernacular n a m e s Water-willow (En). Indonesia: sobah (Javanese), jurai (Sundanese), sangkir (West Sumatra). Malaysia: kelereh, mempenai, kayu suarah. Philippines: agukuk, agoyoi, managos (Tagalog). Burma (Myanmar): momakha. Cambodia: réi tük. Laos: kh'aiz fa:d. Thailand: khrai-nam, khrai-hin (peninsular), khrai (central, northern). Vietnam: ru ri, ri ri, cay ru ri nuoc. Origin and geographic distribution H. riparia is widely distributed in Asia from India through Indo-China and southern China to Taiwan and from Peninsular Malaysia, throughout Indonesia and the Philippines to Papua New Guinea. U s e s Because of its long and extended root system H. riparia is planted along rivers and streams to stabilize and protect the banks. Stems and branches provide firewood. In southern China the bark is used as rope. Leaves are eaten as a vegetable in the Philippines and can be used for fodder as well. In Sabah the root is used to make handles. H. riparia provides a number of popular local medicines. In Laos, a decoction of the leaves is used against itches. In Cambodia, the stems and leaves are applied as a purgative, whereas an infusion of the wood is used against malaria and scabies. In Java, leaves were used to blacken teeth and to fix loose ones. The pounded leaves and sometimes fruits are applied as a poultice against skin diseases in Malaysia, Thailand and Cambodia. A decoction of the leaves and fruits is similarly effective. Young shoots and leaves are a component ofa hair oil in Cambodia. Properties Seeds contain a fatty oil.Most parts of the plant have a high tannin content. The bark contains cyanogenic glycosides. The grey-brown wood is moderately hard and close-grained. Botany A gregarious shrub or small, crooked and twisted tree, 1-4 m tall, up to 10 cm in stem diameter, forming a woody, deep and extensive

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root system. Branches smooth to slightly grooved. Leaves alternate, simple; stipules keel-like, enlarged at base, 5-6 mm long, caducous; petiole 5-15 mm long, pubescent; blade narrowly lanceolate to oblong, 4-20 cm x 1-2.5 cm, obtuse or rounded at base, acuminate, obtuse or mucronate at apex, bright green, penninerved, thin, chartaceous, upper surface shiny, glabrous, lower surface pubescent, closely glabrescent and minutely lepidote, margin entire or dentate. Male inflorescence an axillary, densely-flowered spike, 5 cm long or more, pubescent; peduncle grooved; bracts triangular, acuminate; flowers solitary, axillary, with two lateral, sterile bracteoles; sepals 3, minute, mucronate; stamens numerous, united in fascicles or bundles which at base are connate into a common trunk, unilocular. Female inflorescence an elongated, pauciflorous spike, to 7 cm long; flowers sessile, axillary, bracteate; sepals 5, ovate, 1.5-2 mm long, acuminate, imbricate, abaxially puberulous; ovary globose, trilocular, 2 mm in diameter; style tripartite, 5 mm long, strongly papillate, basally united over a short distance. Fruit a

Homonoia riparia Lour. - 1, fruiting branch; 2, part of male inflorescence; 3, male flower.

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globose capsule, 4 mm in diameter, puberulent, tricoccous. Seed ovoid, 2 mm long, crustaceous. In seasonal climatic conditions H. riparia is deciduous. In Vietnam it flowers from April to June and fruits from August to October. In West Java flowering and fruiting is from June to November, in Central Java it flowers from June to October and fruits from September to April. Most plants are unisexual, but sometimes male and female flowers can be found on the same plant. Ecology H. riparia is restricted to river banks, lake shores and rocky stream beds, from 50-500 m altitude. In its natural habitat it is regularly flooded, at least annually. Its extended root system protects it against uprooting during floods; even floods that completely submerge the shrub during the rainy season for up to 9 months per year can be withstood (such plants are called 'rheophytes'). It is found under ever-wet and seasonal climatic conditions, preferring exposed sunny sites on stream banks and in stream beds in not too deep or too swift streams. As to the stream bed soil, H. riparia seems to have no preferences; it occurs on sand, granite, shale, andesite, and other volcanicderived material, but also on calcareous soil. Agronomy Since H. riparia is only occasionally planted on river banks hardly any information on its cultivation is known to exist. It can be propagated by seed and by cuttings. Genetic resources and breeding It is unlikely that any germplasm collections ofH. riparia are being maintained. Prospects H. riparia is a good source of firewood because the woody roots, stems and branches are hard and have a high energy value. Its strong and extended root system and strong, branched stem make it a useful plant to protect river banks. Its strong bark is worth testing for fibre. Literature 11! Airy Shaw, H.K., 1982. The Euphorbiaceae of Central Malesia (Celebes, Moluccas, Lesser Sunda Islands). Kew Bulletin 37: 25. 121Gagnepain, F., 1925. Homonoia. In: Lecomte, H. & Gagnepain, F. (Editors): Flore générale de l'Indochine [General flora of Indo-China]. Vol. 5. Masson, Paris, France, pp. 330-333. I3l Loc, Phan Ke, 1973. List of tannin containing plants in North Vietnam. Bio-Geographical Journal (Hanoi) 11: 1-44. 141 Pételot, A., 1954. Les plantes médicinales du Cambodge, du Laos et du Vietnam [The medicinal plants of Cambodia, Laos and Vietnam]. Vol. 3. Archives des recherches agronomiques et pastorales du Vietnam No 22. Centre Na-

tional de Recherches Scientifiques et Techniques, Saigon, Vietnam, pp. 85-86. I5l van Steenis, C.G.G.J., 1981. Rheophytes of the world. An account of the flood-resistant flowering plants and ferns and the theory of autonomous evolution. Sijthoff & Noordhoff, Alphen aan den Rijn, the Netherlands. 407 pp., particularly pp. 241-247. Nguyen Nghia Thin

Indigofera hendecaphylla Jacq. Collectanea 2: 358 (1789). LEGUMINOSAE - PAPILIONOIDEAE

2n =16 (diploid), 32 (tetraploid) Synonyms Indigofera celebica Miquel (1855), I. siamensis Hoss. (1907), I. spicata Forssk. sensu auct. mult. Note: I. hendecaphylla is often misspelled/, endecaphylla. Vernacular n a m e s Creeping indigo (En). Trailing indigo (Am). Indigotier rampant (Fr). Indonesia: basingan, sibar (Sumatra), baleh angin (Sulawesi). Thailand: khram-khrua (northern). Vietnam: ch[af]m b[uj]i. Origin and geographic distribution I. hendecaphylla occurs naturally in Africa, Madagascar, throughout South and South-East Asia and in Papua New Guinea. It was taken into cultivation in Java and Peninsular Malaysia in 1923 from Sri Lanka. Cultivation spread from Java to the Philippines in 1927. 7. hendecaphylla has been grown experimentally in Australia and has become naturalized in northern Queensland. Later, it was brought to the Americas, where it is widely cultivated in Hawaii, Jamaica, Puerto Rico, and Florida. Uses I. hendecaphylla provides a good soil cover and smothers weeds. In tea estates in Sri Lanka I. hendecaphylla was the most popular green manure and cover crop. In Indonesia and Peninsular Malaysia it is used as a cover crop in rubber, sisal, oil palm and tea plantations; in Africa in coffee plantations. Some strains of/, hendecaphylla, especially those from Africa, provide valuable and palatable fodder, but the leaves and seeds of other strains are highly hepatotoxic. Properties Tests in Sri Lanka and Indonesia indicate that green material contains per 100 g dry matter: organic matter 87.4 g, ash 12.6 g, N 3.1 g, P 0.2 g, K 1.3 g, Ca 2.6 g. Analysis of the leaves and stems used for fodder gave the following values per 100 g dry matter: protein 20.5 g, fat 3.0 g, soluble carbohydrates 39.5 g, fibre 23.5 g, ash 11.0 g; the digestibility of the components

INDIGOFERA

was: protein 76%, fat 67%, soluble carbohydrates 81%, fibre 60%. The leaves of I. hendecaphylla, possibly only of tetraploid forms originally from Sri Lanka, contain per 100 g dry matter 0.1-0.5 g indospicine (2,7-diamino-7-amino-heptanoic acid) while the seeds contain 0.1-2 g. Indospicine is a specific antagonist of arginine, interfering with its synthesis and incorporation into proteins and with the synthesis of DNA. Indospicine is highly toxic to chicken, rabbits, pigs, goats, sheep, cattle and horses. In small doses it causes loss of vitality and abortion in cattle and goats. Indospicine is especially dangerous to horses, which relish plants containing it and eat them preferentially. I. hendecaphylla also contains nitrogenous compounds called endecaphyllins, as well as 3-nitropropionic acid. The weight of 1000 seeds is about 20 g. Description Sub-erect shrublet (20-)40-75 cm tall, gradually becoming prostrate. Main root 50-100 cm x 0.5-1 cm, white. Stem creeping, up to 2 m long, rooting at the nodes, pale green to yel-

Indigofera hendecaphylla Jacq. - 1, flowering and fruiting branch; 2, leaf with one inverted leaflet; 3, flower; 4, calyx and staminal sheath.

157

low, tough; branches ascending, striate, with appressed, biramous hairs with equally long arms. Leaves pinnate, alternate, 3-5 cm long; stipules narrowly triangular, apex caudate, 5-6 mm x 1.5-2.0 mm; petiole 1-3 mm long; leaflets 9-11, shortly petioluled, alternate, sometimes almost opposite, narrowly oblong-elliptical to narrowly oblanceolate, 3-20 mm x 2-9 mm, apex rounded, mucronate, upper surface subglabrous. Inflorescence an axillary raceme, 5-17(-23) cm long; flowers 4-6 mm long, crowded, brick red to pink, occasionally purple or white; pedicel about 1mm long; calyx tube 1.5 mm x 1.5 mm, teeth narrowly triangular, 2.5—3 mm long; standard broadly ovate 4.0-5.5 mm x 3.0-4.0 mm, strigose on the back; wings 3.0-4.5 mm x 1.5-2.0 mm, glabrous, margins long-ciliate along the upper auricle; keel 3.5-5.0 mm x 2.0-2.5 mm, hairy, margin ciliate, lateral pocket 1 mm long; staminal tube 4-5 mm long, apex rounded to obtuse, anthers 0.5 mm x 0.5 mm; ovary glabrous. Fruit a descending, straight, needle-like, dark brown pod, stiff, somewhat quadrangular to round in cross-section, 2.0-3.5 cm x 2-2.5 mm, 5-10-seeded, beak 2 mm long, endocarp not blotched. Seed very small, cubic to quadrangular-ellipsoid, 2 mm x 1 mm, yellowish to dark brown. Growth a n d development Seedlings develop a strong taproot which assists in loosening the soil. When cuttings are used for planting I. hendecaphylla remains very low, the cover rarely exceeding 12 cm in height. A fair cover can be formed in 6 months and a continuous even cover in a year from planting. The plants send out trailing stems which, under favourable conditions, may attain a length of 2 m, producing numerous adventitious roots at the nodes. As the plants mature they become taller and at 2 years of age they are usually about 30-40 cm tall. Vigorous regrowth occurs at the start ofthe rainy season. Other botanical information I. hendecaphylla and I. spicata Forssk. used to be considered as the same species and were then named I. spicata. They are now considered to be different species. The literature is therefore confusing, and references to toxicity most probably refer to I. hendecaphylla. In I. hendecaphylla the staminal tube is 4-5 mm long, distinctly longer than the calyx, the apex of the keel rounded to obtuse, and leaves have 9-11, narrowly oblong-elliptical to narrowly oblanceolate leaflets. In I. spicata the staminal tube is 3-3.5 mm long, not exceeding the calyx, the keel apex acute, while the leaves have 5-8 obovate leaflets with cuneate base. I. spicata is re-

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AUXILIARY PLANTS

stricted to Africa and Yemen, often in the drier regions. I. hendecaphylla occurs pantropically, often in more humid areas; it is a very variable species and many varieties have been described, distinguished by leaflet form and hairiness. These distinctions are not considered useful, because many intermediate forms occur. Ecology I. hendecaphylla thrives from 0-700 m altitude and is found to about 2500 m. It requires an average annual temperature of 16-27°C and an annual rainfall of 600-1500 mm, but may be found in wetter locations receiving up to 4000 mm annual rainfall. In cultivation it is fairly resistant to drought and shade. Under heavy shade, as in old rubber plantations, growth is poor. I. hendecaphylla performs best on clay soils, but grows on various soil types, including sandy soils, with a pH of 5.0-7.7. It is tolerant of poor, moderately acid, P-deficient soils. Soil covers of /. hendecaphylla are notorious for harbouring snakes and leeches. Propagation I. hendecaphylla can be propagated by seed and by stem cuttings. Seed is very hard and germinates poorly without scarification. Mechanical scarification and treatment with sulphuric acid for 40-60 minutes can increase the germination rate to about 80%. To obtain a good distribution ofthe seed it is mixed with sand or filtered dry soil at a ratio of seed to sand of 1 :4 before sowing. If planted in rows 60 cm apart the seed rate is about 3.3 kg/ha. Cuttings are used when seed is difficult to obtain. For large-scale plantings, they should be raised in nurseries. Cuttings of about 20 cm long are planted at a spacing of60 cm x 60 cm with 5 cuttings per hole. Once established, I. hendecaphylla is self-sowing. Husbandry The maximum effect oil. hendecaphylla as a green manure is reached when the cover crop is incorporated in the soil when still green and flowering has started. Green manure crops produce 4.5-25 t/ha of green material. In trials in Indonesia I. hendecaphylla has produced a green matter yield of 3.0 t/ha 3 months after planting, containing 10 kg nitrogen and 3 kg phosphorus. After 6 months the green matter yield was 18 t/ha, containing 86 kg nitrogen and 21kg phosphorus. A cover crop of I. hendecaphylla controls erosion effectively on hilly and undulating land even under heavy rainfall, and is considered more effective than Clitoria ternatea L. Few weeds, except some grasses, can grow through this cover and, once established, a reduction in weeding costs may be anticipated. Weeds such as Mikania spp. and Convolvulus spp. can cause some trouble.

When ring-weeding around young tea plants the stems of/, hendecaphylla have to be cut, as these are otherwise difficult to incorporate into the soil. Diseases and pests I. hendecaphylla is remarkably free from diseases. The only important pest in Sri Lanka is the caterpillar Dichomeris ianthes, which sometimes completely defoliates the crop; however, it normally recovers very quickly. In Peninsular Malaysia, the plant is liable to attacks by the larvae of a small moth, probably Lamprosema diemenalis, but the damage is not permanent. Genetic resources and breeding A germplasm collection of Indigofera L. is being maintained at the Southern Regional Plant Introduction Station of the United States Department of Agriculture, Griffin, Georgia containing a few accessions of I. hendecaphylla. Strains with a reduced indospicine content have been bred in Australia, but indospicine-free material has not yet been obtained. Prospects I. hendecaphylla remains an excellent cover crop, providing a dense, well-rooted, low cover in humid areas. In drier areas growth is too slow. More research is needed on the variation in indospicine content, its relation with polyploidy and its presence in African material. Strains from Africa that have been used as fodder crop may be developed into cover crops safe for farm animals. Literature 111 Aylward, J.H., Court, R.D., Haydock, K.P., Strickland, R.W. & Hegarty, M.P., 1987. Indigofera species with agronomic potential in the tropics. Rat toxicity studies. Australian Journal of Agricultural Research 38: 177-186. 121 de Kort, I. & Thijsse, G., 1984. A revision of Indigofera in South-East Asia. Blumea 30: 89-134, in particular 132-134. 131 Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 98-99. 141 du Puy, D.J., Labat, J.-N. & Schrire, B.D., 1993. The separation of two previously confused species in the Indigofera spicata complex (Leguminosae: Papilionoideae). Kew Bulletin 48: 727-733. 151Morton, J.F., 1989. Creeping indigo (Indigofera spicata Forssk.) (Fabaceae) - hazard to herbivores in Florida. Economic Botany 43(3): 314-327. 161 Smolenski, S.J., Kinghorn, A.D. & Balandrin, M.F., 1981. Toxic constituents of legume forage plants. Economic Botany 35(3): 321-355. B. Sunarno

INDIGOFERA

I n d i g o f e r a h i r s u t a L. Sp.pl.: 751 (1753). LEGUMINOSAE - PAPILIONOIDEAE

2« = 16 Synonyms Indigofera indica Miller (1768), I. ferruginea Schum. & Thonn. (1829), I. angustifolia Blanco (1837). Vernacular n a m e s Hairy indigo (En). Rough hairy indigo (Am). Indigotier hérissé (Fr). Indonesia: tom-toman, jukut lulut (Java), tebawang amjak (Sulawesi). Malaysia: cermai burong. Philippines: tayom (Iloko), tagum (Bisaya), tina-tinaan (Tagalog). Papua New Guinea: tildjil, wiereka. Thailand: khram-khon (northern). Vietnam: c[aa]y c[or] ch[af]m, c[aa]y s[uj]c s[aj]c ma, ch[af]m l[oo]ng. Origin and geographic distribution I. hirsuta is native to Asia and Africa. It was cultivated as a green manure in Bogor in the 19th Century and was first tried as such in Malaysia in 1913. It was introduced into the United States in 1908 and proved suitable for cultivation in the coastal regions of Florida and Texas. It is now cultivated throughout the tropics. Uses I. hirsuta is a valuable green manure and cover crop, used especially in tea, coffee and rubber plantations. Research interest in hairy indigo as a cover crop or green manure in South-East Asia has been limited in recent years. In Florida it is often considered a weed in row-crop fields, but in citrus plantations it is grown as a cover crop. It is used especially where erosion control is important. It is grown as an annual fodder in Florida and Brazil and in mixtures with grasses as a forage crop. A decoction made from the leaves is used against stomach problems in the Philippines, and against yaws in Ghana. In West Africa it has occasionally been used as a dye. Properties Per 100 g dry matter, leaves contain: N 2.14 g, P 0.12 g, K 1.53 g, and Ca 3.00 g. Hay cut at the flowering stage contains per 100 g: moisture 10.7 g, crude protein 13.7 g, crude fat 1.4 g, N-free extract 46.0 g, fibre 21.0 g, ash 7.2 g; digestibility coefficients are: dry matter 62.5%, protein 67.0%, fat 61.0%, N-free extract 67.0%, fibre 53.5%. Cattle do not graze hairy indigo readily, but intake is good after adaptation. It is somewhat toxic and should not constitute a large proportion of the diet. Cattle grazing on it for extended periods of humid weather may develop sores on their feet and legs. It is believed that the hairs of the plants irritate their wet skin.

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The weight of 1000 seeds is 1.5-2.5 g. Description Annual herb or subshrub, up to 1.5 m tall, covered with conspicuous brown hairs, which are biramous and spreading with very unequally long arms, looking almost simple. Branches erect, striate, becoming woody at seed maturity. Leaves imparipinnate; stipules narrowly triangular to linear, 10-12 mm long; petiole 2-5 cm long; rachis up to 9 cm long; stipels 1-2 mm; petiolule 1.5-3 mm long; leaflets 5-11, opposite, elliptical to obovate, terminal one 2.5-3.5(-6) cm x l-2(-3) cm, lateral ones 1.5-3 cm x 0.7-1.5 cm, base cuneate, apex rounded, mucronate, hairy to strigose on both surfaces, veins distinct, main vein brown. Inflorescence a densely flowered raceme, (3-)10-30 cm long; bracts linear-triangular, about 4 mm long, caducous; peduncle 3 cm or longer; pedicel about 2 mm long; flowers up to 6 mm long; calyx about 4 mm long, with stiff brown hairs, divided almost to the base into linear, setaceous

Indigofera hirsuta L. - 1, flowering and fruiting branch; 2, flower; 3,fruiting branch.

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lobes; corolla red to pink; standard elliptical, 4-5 mm x 2-2.5 mm, emarginate at apex; white pubescent outside; wings 4-5 mm x 1.5 mm, hairy at upper margin; keel 4-5 mm x 1.2-1.5 mm, upper margin with hairs, lateral pocket 0.7 mm long; staminal tube 4.5 mm long; anthers 0.4 mm long; ovary hairy with 6-9 ovules. Fruit a reflexed, straight pod, rounded to tetragonal in cross-section, 1-2 cm x 1-2.5 mm, with well developed sutures, and with long spreading hairs, dehiscent, (4-)6-9-seeded, endocarp blotched. Seed cuboid, 1 mm long, brown, distincly pitted. Growth and development Early growth of seedlings is very slow. Weeding is therefore only possible after 4-6 weeks, when plantlets can be distinguished from weeds. Under suitable conditions the plants reach a height of 30 cm after about 50 days, 60 cm after 65 days and 90 cm after about 80 days. In Sri Lanka, I. hirsuta flowers and fruits from September to February and in the United States it flowers late in the growing season, producing a good green manure or forage crop before seed maturation. Pollination is by insects. Hairy indigo fixes atmospheric nitrogen symbioticallywith cowpea-type rhizobium. Other botanical information I. astragalina DC. is sometimes included in I. hirsuta, forming a single, polymorphic species. I. astragalina usually has more leaflets than I. hirsuta, often whitish hairs, a shorter peduncle and paler flowers. It occurs in the Sudano-Sahel zone, south-eastern Africa, Pakistan, India, Sri Lanka and Burma (Myanmar). Where both species occur in the same region, I. hirsuta occupies the wetter areas. Genetic diversity in hairy indigo is greatest in Africa, from where cultivars have been reported showing tolerance to diseases, pests, weeds, low pH, poor soil, and shade. Ecology I. hirsuta occurs as a weed in cultivated and waste areas, in grassland, savanna, dry and deciduous forest, on river banks and beaches, at 0-1500 m altitude. It requires an annual rainfall of 900-2500 mm and an annual mean temperature of 15-28°C. It does not tolerate frost. A dry season stimulates flowering and seed production. Although generally fairly tolerant to shade, growth under heavy shade in an established stand of pine trees in Costa Rica was poor. Hairy indigo is tolerant to poor soil conditions, growing well on moderately poor, sandy soils with low pH, and on slopes. It requires moderately to well-drained soils with a pH of 5-8 and is intolerant of waterlogging. Propagation a n d planting I. hirsuta is propagated by seed. Germination percentage is often

low, but can be improved by hot water treatment (70-80°C for 20-30 minutes). Seed of early selections is smaller than that oflater ones. In Florida, hairy indigo is sown from early to late spring, with early sowing being preferred. When drilled in closely spaced rows a seeding rate of 3-5 kg/ha is used; when broadcast in a well firmed seed-bed 6-10 kg/ha of seed is needed. Lower rates are recommended for seed production. Seed should preferably be sown at a depth of 1 cm, but may be broadcast without any follow-up soil cultivation. Trampling by cattle and rain will result in the seed being covered sufficiently. Seed germinates after 7-9 days. Under grazing in Florida, hairy indigo is a self-regenerating annual, even in fields that are burned or disked. In permanent, mixed pastures, cattle need not be removed during the period of seed development. Reducing grazing intensity is sufficient to produce enough seed for a volunteer crop. Disturbing the soil superficially results in a better volunteer crop. Husbandry In the United States, weeding and earthing up is done 1-1.5 months after planting and again 1 month later. Cover crops in tree-crop plantations are slashed at regular intervals. Slashing and lopping is tolerated well. Phosphate and potash applications increase growth, recommended amounts in Florida are: P 2 0 5 30-70 kg/ha and K 2 0 30-50 kg/ha. Hairy indigo can be relayplanted in maize. When planted 40 days after germination of maize, it produces a dense soil cover soon after the maize harvest, yielding 4-5 t dry matter per ha containing about 100 kg of nitrogen. Established mixed grasslands should be grazed closely at the beginning of the growing season until I. hirsuta germinates and establishes itself. Diseases and pests I. hirsuta exhibits some tolerance to most diseases and pests. The following fungi have been reported as occurring on hairy indigo but without causing serious dieseases: Colletotrichum dematium, Corticium solani, Rhizoctonia solani, and Sclerotium rolfsii. It has shown extensive tolerance to root-knot and sting nematodes. Experiments indicate that hairy indigo in a rotation markedly reduces the numbers of several Meloidogyne spp. Genetic variation in tolerance and antagonistic effects to nematodes is considerable and should be further investigated. Harvesting I. hirsuta can be harvested as common hay crops with ordinary farm equipment. It should be cut early when 75-90 cm tall. If cut early when 20-25 cm tall before flowering, a second growth may be expected. The regrowth may then

INDIGOFERA

be used forgrazing orhay. Grazing should be rotational, toprevent severe removal of leaves. Seed canbe harvested by cutting the infructescences by hand. Very large plants may be cut with a mowing machine, allowed to dryin windrows and threshed. Stands that arenottooheavycan be combine harvested. Harvesting should be done when seed is mature, butbefore shattering. Seed set is abundant. In the United States seed of large-seeded strains matures in late autumn, while smaller-seeded strains mature 3-4 weeks earlier. Yield In Florida green matter yields of I. hirsuta average about 22t/ha (13 t/ha dry matter)and in coconut plantations in India 10 t/ha. Seed yields average 100-300 kg/ha. Noinformation is available onyields in South-East Asia. In Florida in mixed stands with pangola grass (Digitaria eriantha Steudel) orBahia grass {Paspalum notatum Flueggé), annual dry matter yields of about 5.5 t/ha are obtained with an average crude protein content of about 10%. Forage yields were lower than those ofmixtures with Desmodium intortum (Miller) Urban, D. heterocarpon (L.) DC.and Macroptilium atropurpureum (DC.) Urban. Genetic resources A small germplasm collection of I. hirsuta is maintained by the United States Department ofAgriculture in Florida and at the Southern Regional Plant Introduction Station, Griffin, Georgia. Breeding Very little breeding work has been done in /. hirsuta. Early andlate-maturing lines were developed in Florida intheearly 1940s,but they nolonger exist. New early ('FL-24') and late ('Fl-101') cultivars were released in 1988. Prospects The strong ability to reseed itself and its development late in the season make /. hirsuta agood green manure inannual crops. Further selection work isneeded toinvestigate itspotential to produce high organic matter yields. Its efficacy toreduce nematode infestation needs further investigation. Literature 111 Backer, CA. & Bakhuizen van den Brink, R.C., 1963.Flora of Java. Vol. 1. Noordhoff, Groningen, theNetherlands, p.591. I2l Baltensperger, D.D.,French, E.C.,Prine,G.M., Ruelke, O.C. & Quesenberry, K.H.,1985. Hairy indigo, a summer legume for Florida. University of Florida, Gainesville, United States. 11pp.131 De Kort, I. &Thijsse, G., 1984. A revision of Indigofera in Southeast Asia. Blumea 30: 120-121. I4i Kalmbacher, R.S., Mislevy, P.&Martin, F.D., 1981. Minerals in the forage of American jointvetch andhairy indigo asaffected by harvest

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height. Proceedings ofthe Soil andCrop Science Society of Florida 40: 124-127. I5l Perry, L.M., 1980. Medicinal plants of East and South-East Asia. Massachusetts Institute of Technology Press, Cambridge, Massachusetts, United States, p. 218. 161 Rodriguez-Kabana, R.,Robertson, D.G., Wells, L. &Young, R.W., 1988. Hairy indigo for the management of Meloidogyne arenaria in peanut. Nematropica 18: 137-142. 171 Sabiiti, E.N., 1980. Drymatter production and nutritive value of Indigofera hirsuta L. in Uganda. East African Agricultural and Forestry Journal 45: 296-303. T. Djarwaningsih

Indigofera suffruticosa Miller Gard. Diet. ed. 8,No 2(1768). LEGUMINOSAE - PAPILIONOIDEAE

2n = 12,16 Synonyms Indigofera anil L. (1771). Vernacular n a m e s Anil indigo (En). Anil de pasto (Am). Indonesia: taem-taem (Sumatra), tagom-tagom (Kalimantan), torn janti (Javanese). Malaysia: tarom, sekebak (Peninsular Malaysia). Philippines: tina-tinaan (Tagalog), tayum (Bisaya, Ilokano), sangifaria (Mindanao). Thailand: khram-thuan (Shan, Chiang Mai), khram yai (Ubon Ratchathani). Vietnam: ch[af]m b[uj]i, c[aa]y ch[af|m. Origin and geographic distribution I. suffruticosa originated in tropical America, but is now widely distributed andnaturalized throughout the tropics, including South-East Asia. Uses I. suffruticosa is used mainly in Java and Sri Lanka as a cover crop and green manure in coffee, rubber and tea plantations. InSouth America itisone of the components of natural pastures developing after clearing rain forest. It has been widely cultivated as a dyeplant yielding indican from which indigo is prepared. Its cultivation for local use still continues on a small scale. In Malaysia a decoction ofthe roots istaken against stomach-ache, an infusion of bruised leaves against fever and plant juice against diarrhoea.In China a mixture ofthe leaves of/, suffruticosa, I. tinctoria L., the bark of Phellodendron chinense C.K. Schneider andpig bile is used asa medicine against scrofula. Production and international trade I. suffruticosa is still grown for dye on a very small scale inJava, Karnataka (India), Africa andCentral America, but no statistics exist.

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Properties In Hawaii fresh material of I. suffruticosa grown as a green manure has a nitrogen content per 100 g dry matter of 1.6-3.1 g in the above-ground parts, and 1.4-2.4 g in the roots. Plants contain the glucoside indican, which transforms into indoxyl (indigo-white) and glucose by enzymatic hydrolysis. Indoxyl can be oxidized to indigo-blue. An aqueous extract ofthe fruit has an hepatotoxic effect and causes chromosome aberrations in mice. The weight of 1000 seeds is about 4 g. Description Shrub, 45-250 cm tall with erect, striate branches and with indumentum of appressed, biramous hairs with equally long arms. Leaves imparipinnate; stipules narrowly triangular, 3-6 mm x 0.2-0.3 mm; petiole up to 2 cm long; rachis 5-10 cm long; petiolule 1-1.5 mm long; stipels linear; leaflets opposite, (7-)9-15, narrowly elliptical to narrowly obovate, 10-40 mm x 3-15 mm, base cuneate, apex acute to rounded, mucronate, glabrous or with very few hairs above, appressed grey pubescent beneath. Inflorescence an

Indigofera suffruticosa Miller - 1, flowering and fruiting branch; 2, flower; 3, stamens; 4, infructescence;5,pod; 6, seeds.

axillary raceme, 2-6 cm long; bracts narrowly triangular; pedicel 0.5-1 mm long; flower 4-5 mm long, salmon pink to red; calyx campanulate, tube 1 mm long, teeth triangular, 0.7-1.2 mm long; standard ovate to orbicular, 3-4.5 mm x 2.5-3 mm, hairy on the back; wings 2-4 mm x 0.8-1.2 mm, glabrous; keel 2.5-4.5 mm x 1.2-2 mm, hairy, margins not ciliate, lateral pocket 0.5 mm long; stamens 10, 1free, 9 connate into a staminal tube 3.5-4 mm long; ovary hairy, style with capitate stigma. Fruit a descending pod, 4-6-seeded, distinctly upcurved, 1.5-2(-3) cm x 2 mm, hairy. Seed cubical, 1.5-2.0 mm x 1.5 mm, shiny brown. Seedling with epigeal germination. Growth and development The first leaves formed after germination are simple. Seedlings quickly develop a deep root system. I. suffruticosa may occasionally overgrow young tea plants, but can be removed very easily as it neither winds nor climbs. Flowering starts early, at an age of 4-5 months. After 4-5 loppings in 2-2.5 years, plants tend to die out. Other botanical information Two subspecies are recognized in I. suffruticosa: subsp. suffruticosa and subsp. guatemalensis (Mocino, Sessé & Cerv. ex Backer) de Kort & Thijsse (synonym: I. guatemalensis Mocino, Sessé & Cerv. ex Backer). Subsp. guatemalensis occurs naturalized in Thailand and Vietnam and is cultivated in Java where it is sometimes adventive, but where it does not naturalize; it can be distinguished by its smaller leaves and flowers (to 3 mm long) and straight, 1-3-seeded pods; its branches are not striate. I. suffruticosa closely resembles I. arrecta Höchst, ex A. Rich, (taller, less bushy and always with straight pods) and 7. tinctoria L. (smaller, pods smaller, straight or slightly curved, 7-12-seeded). It is possible that these 3 species sometimes hybridize. Ecology I. suffruticosa is commonly found on roadsides, waste land, fallow land and cultivated fields up to 1800 m altitude. It is sometimes found on beaches and in grass fields. Propagation Seed and stem cuttings are used for propagation. Sowing is done either in seedbeds or directly into the field. Seed should be soaked in water overnight for optimal germination. In direct planting seeds are sown in continuous lines about 30 cm apart or 3-4 together in holes 45 cm x 60 cm apart. Germination takes 4-6 days. When a seed-bed is used the seedlings can be transplanted 4-6 weeks after sowing. Cuttings are taken from well developed branches divided into 30 cm long pieces. They are kept for 2-3 days

IPOMOEA

in a cool place before planting out, 2-3 per hole. Rooting starts in the second week. Husbandry After sowing or planting, weeding is necessary. In I. suffruticosa cover crops, weeding is mostly done selectively. Some weeds are left like Centella asiatica (L.) Urb. and Drymaria glandulosa Bartl. as they also are valuable cover plants and help in checking erosion. Lopping can be started when the plants have a height of 50 cm, leaving about 25 cm. Agood cover of/, suffruticosa can increase the nitrogen content of the soil considerably. In Sri Lanka for example, an increase from 3.7% to 5.3%in 4 years was found. Diseases and pests No serious diseases or pests have ever been reported to attack I. suffuticosa. In humid conditions Corticium salmonicolor sometimes affects the stems after slashing. Genetic resources and breeding Polyploid strains of/, suffruticosa seem to exist. A collection of Indigofera germplasm is being maintained at the Southern Regional Plant Introduction Station of the United States Department of Agriculture, Griffin, Georgia, which includes several accessions of/, suffruticosa. Prospects /. suffruticosa forms in a short period a dense and well-rooted soil cover and is an excellent cover crop that deserves more attention from research and extension. Literature 111 Chow, K.H., 1976. Morphology and ecology of some wild herbaceous legumes in Singapore. Journal of the Singapore National Academy of Science 5: 20-30. 121 de Kort, I. & Thijsse, G., 1984. A revision of Indigofera in South-East Asia. Blumea 30: 89-151. I3l Lemmens, R.H.M.J. & Wessel-Riemens, P.C., 1991. Indigofera L. In: Lemmens, R.H.M.J. & WulijarniSoetjipto, N. (Editors): Plant Resources of SouthEast Asia No 3:Dye and tannin-producing plants. Pudoc, Wageningen, the Netherlands, pp. 81-83. 141Rembert, D.H., 1979. The indigo of commerce in colonial North America (Indigofera caroliniana, Indigofera tinctoria, Indigofera suffruticosa). Economic Botany 33: 128-134. I5l Ribeiro, L.R., Bautista, A.R.P.L., Silva, A.R., Sales, L.A., Salvadore, D.M.F. & Maia, P.C., 1991. Toxicological and toxicogenetic effects of plants used in popular medicine and in cattle food. Memorias do Institute Oswaldo Cruz 86, Suppl. 2: 89-91. l6l Sanjappa, M., 1987. The Indigoferas of Sri Lanka. Journal of Economic and Taxonomie Botany 10: 329-346. B. Sunarno

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I p o m o e a L. Sp.pl.: 159 (1753). CONVOLVULACEAE

x = 15;/. littoralis: 2« = 30, 60; /. pes-caprae: 2n = 30, 22-31 Major species and synonyms -Ipomoea imperati (Vahl) Griseb., Cat. pi. Cub.: 203 (1866), synonyms: Convolvulus sinuatus Petagna (1787),Ipomoea stolonifera (Cirillo) J.F. Gmelin (1791),/. carnosa R. Br. (1810). - Ipomoea littoralis Blume, Bijdr.: 713 (1825), synonym:/. denticulata (Desr.) Choisy (1834). - Ipomoea pes-caprae (L.) R. Br., Tuckey, Narr, exped. Zaire: 477 (1818), synonyms: Convolvulus pes-caprae L. (1753), Ipomoea biloba Forsk. (1775),/. maritima (Desr.) R. Br. (1810). Vernacular n a m e s General: ipomoea (En). - /. imperati: Little horse's foot print, white-flower beach morning glory (En). Indonesia: klemut, kangkungan (general), krangkungan (Javanese). Thailand: phakbung-thale (central). - /. littoralis: Little horse's foot-print (En). Indonesia: akar hitang (Palembang), kangkung laut (Bangka), loboke ma loha (Halmahera). Malaysia: kangkong, tapak kuda kecil (Peninsular). Philippines: bulukan (Tagalog), malakamote (Ibanag), panggi-panggi (Sulu). Thailand: chingcho lek (Peninsular). - / . pes-caprae: Beach morning glory, horse's footprint, goat's foot creeper (En). Bay-hops (Am). Indonesia: daun katang, tapak kuda (general), katang-katang (Bali). Burma (Myanmar): pinlaikazum. Cambodia: trakuon kantek, pak bung tale. Thailand: phakbung-thale (central). Vietnam: rau mu[oos]ng bi[eer]n. Origin and geographic distribution Ipomoea comprises about 500 species occurring throughout the tropics and subtropics, the majority in America and Africa. /. imperati is pantropical, rather rare in Malesia, but occurring in Peninsular Malaysia, Madura and the Philippines, /. littoralis is confined to the tropics of Asia, Australia and the western Pacific, /. pes-caprae is one of the most common beach plants throughout the tropics, including South-East Asia. Uses The species treated here live on sandy beaches and act as sand binders by checking erosion and drifting of sand in wind-swept areas. They contribute to the accretion of land and facilitate the establishment of other plants. /. pescaprae has been used successfully to revegetate mine spoil. Its seeds are used as a remedy for stomach-ache and cramp. In East Malaysia the

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leaves are made into poultices and applied to ulcers, swellings and wounds, and also against rheumatism. In Kambangan Island, south of Central Java, and in Thailand, thejuice from the stem is used to treat the sting ofjellyfish and toadfish, elsewhere it is taken as a diuretic. The leaves are given as a fodder to pigs, but if eaten by dairy cows their milk is spoiled. Young leaves of I. imperati are eaten as a vegetable by the Madurese, while those of I. littoralis were eaten in times of famine in the Pacific. Flowers of the latter are used in garlands. Properties The seed of the three Ipomoea spp. contain glycoside resins. An aqueous extract of the stems and leaves reversibly counteracts the spasmodic effects ofthe poison ofjellyfish. Description Herbs or shrubs, usually twining, sometimes prostrate, floating or erect. Leaves mostly with petiole, alternate, variable in shape and size, entire, lobed or divided. Inflorescence mostly in axillary, one to many-flowered dichasia; flowers small to large; sepals 5, herbaceous or coriaceous, persistent, often somewhat enlarged in fruit; corolla regular, usually funnel-shaped or campanulate; limb 5-lobed; mid-petaline bands well-defined by 2 distinct veins; stamens 5, inserted near base of corolla tube, not exserting the corolla, filaments often unequal in length; ovary 2(-4)-locular, with 4(-6) ovules; style 1, simple, filiform, not exserting the corolla. Fruit a globose or ovoid capsule, 4(-6)-valved, 4(-6)-seeded. - 7. imperati. Perennial, glabrous vine. Stem trailing, rooting at the nodes, terete, up to 5 m long. Leaves fleshy, very variable in shape, even on the same plant; petiole 0.5-4 cm long; blade linear, lanceolate, ovate or oblong, 1.5-4(-8) cm x l-3(-5) cm, margin entire or undulate, base truncate, obtuse or cordate, apex obtuse to emarginate or 2-lobed; blade sometimes 3-7lobed. Inflorescence axillary, l(-3)-flowered; peduncle 12-15 mm long; pedicel 8-15 mm long, in fruit up to 25 mm; bracts minute, linear, 2-3 mm long; sepals oblong, unequal, inner ones 10-15 mm long, outer ones shorter, acute or obtuse, mucronulate, glabrous, subcoriaceous; corolla funnel-shaped, 3.5-5 cm long, glabrous, white, pale yellow inside with a purple centre; filaments hairy at base. Capsule globular, about 1 cm long, smooth, 2-celled, 4-valved, up to 4seeded. Seed trigonous-rounded, 5-9 mm long, short-tomentose, with longer hairs along edges, light brown. - 1 , littoralis. Perennial vine. Stem prostrate and rooting at the nodes or twining, thin, slender,

herbaceous, glabrous, or sometimes sparsely pubescent, woody at the base with age. Leaves coriaceous, glabrous; petiole 0.5-7 cm long; blade broadly ovate to oblong in outline, occasionally orbicular to reniform, 1-10 cm x 1-8 cm, base cordate, apex acute to obtuse, rarely refuse, margin entire, undulate, angular or 3(-7)-lobed. Inflorescence axillary, 1-few-flowered; peduncle 1-9 cm long; pedicel 1-4 cm long; bracts 1-2 mm long; sepals unequal, 2 outer sepals oblong-elliptical to elliptical-ovate, coriaceous, 6-10 mm long, apex acute to obtuse, mucronulate, 3 inner sepals thinner, with membranous margins, suborbicular to sometimes elliptical, 8-12 mm long; corolla funnel-shaped, 3-4.5 cm long, lavender to pinkish-purple, with a darker centre; stamens unequal, filaments 6-12 mm long, hairy at base. Capsule depressed globose, about 1cm in diameter, 4-seeded, sometimes fewer. Seed suborbicular with a notch, 3.5-4 mm long, glabrous, black or dark brown. I. pes-caprae. Perennial, glabrous vine with thick taproot. Stem prostrate, sometimes twining, 5-30 m long, often rooting at the nodes.

Ipomoea pes-caprae (L.) R. Br. - habit flowering plant.

IPOMOEA

Leaves often pointing to one side only; petiole up to 17 cm long; blade variable, ovate, elliptical, circular, reniform, nearly square or oblong, 3.5-10 cm x 3-10 cm, rather thick, with 2 abaxial glands at base of midrib, base broadly cuneate, truncate, or shallowly cordate, margin entire, apex emarginate or deeply 2-lobed, mucronulate. Inflorescence 1-several-flowered; peduncle stout, 3-16 cm long; bracts early caducous, broadly triangular, 3-3.5 mm long; pedicel 1-7 cm long; sepals unequal, somewhat leathery, glabrous, apex obtuse, mucronulate, 2 outer ones ovate-elliptical, 5-9 mm long, 3 inner ones nearly circular and concave, 7-13 mm long; corolla funnel-shaped, 3-6.5 cm long, purple to reddish-purple, with darker inside centre; filaments 7-12 mm long, hairy at base. Capsule globular, 1-1.7 cm in diameter, glabrous, leathery. Seeds 4, trigonous-globose, 6-10 mm long, black, densely brownish tomentose. Growth and development I. pes-caprae is self-incompatible, which is controlled by several genes. Other botanical information I. imperati is better known as /. stolonifera. The nomenclature ofthis taxon is complicated. The oldest valid name is Convolvulus sinuatus Petagna (1787) with Convolvulus stolonifer Cirillo (1788) as homotypic synonym and Convolvulus imperati Vahl (1790) as oldest heterotypic synonym. After being transferred to the genus Ipomoea, the combination I. sinuata was not allowed, because this name had been given to a different species in 1798 by Ortega. The combination I. stolonifer is not permissible because its basionym is an illegitimate name; hence I. imperati is the correct name. /. littoralis Blume used to be considered to be identical to I. gracilis R. Br. The latter, however, is a distinct species; it is quite rare and confined to the northern coast of Australia. In I. pes-caprae, 2 subspecies are recognized: subsp. brasiliensis (L.) Ooststroom (leaf apex emarginate or truncate; leaf base truncate, rounded, attenuate to slightly cordate; outer sepals 5-8 mm, inner ones 7-11 mm long; corolla 3-5 cm long; pantropical, and the most common form in SouthEast Asia) and subsp.pes-caprae (leaf apex deeply lobed with rounded lobes, leaf base cuneate to attenuate; outer sepals 9 mm, inner ones 13 mm long; corolla 6.5 cm long; occurring in Arabia and tropical Asia). Ecology The sand-binding Ipomoea species form a characteristic component of the 'pescaprae' communities on tropical beaches. They

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usually grow in association with Canavalia maritima (Aubl.) Thouars and salt-tolerant grasses and sedges. I. pes-caprae also occurs inland, along roadsides and ditches, up to 800 m altitude. Although these Ipomoea species grow on the beach, they depend on ground water with a lower salt content than sea water. They are tolerant of high temperature, periodic drought, sea water spray, high soil pH and low soil nitrogen content. Propagation Natural propagation of sandbinding Ipomoea species is by seed. The capsules float and are probably dispersed by sea currents. When planted for erosion control, stem cuttings are used, placed 60-100 cm apart, in rows perpendicular to the prevailing wind. Husbandry The 'pes-caprae' formation may form a complete soil cover that traps leaf litter and wind-blown organic material, thus accumulating organic matter and improving soil fertility. Analysis of a beach soil in Sulawesi indicated per 100 g dry soil: C 0.2 g, N 0.03 g, P 3.3 ppm at the edge of the sea, and at a distance of 8 m from the sea: C 1.1 g, N 0.13 g, P 18.6 ppm. Genetic resources A small number of accessions of I. littoralis and I. pes-caprae are maintained at the Southern Regional Plant Introduction Station, Griffin, Georgia, United States. Breeding I. littoralis is one ofthe likely progenitors of/, batatas (L.) Lamk, the sweet potato, and is used in experimental breeding programmes. Prospects Most sand-binding Ipomoea species grow spontaneously on beaches. With more intensive utilization of beaches and the agricultural hinterland, planting may become more important. There is an urgent need for selection of good planting material and research into cropping methods. The species' usefulness for reclamation ofmine spoils also needs further investigation. Literature 111 Austin, D.F., Jarret, R.L. & Johnson, R.W., 1993. Ipomoea gracilis R. Brown (Convolvulaceae) and its allies. Bulletin of the Torrey Botanical Club 120: 49-59. I2l Austin, D.J. & Huâman, Z., 1996. A synopsis of Ipomoea (Convolvulaceae) in the Americas. Taxon 45: 3-38. I3l Craig, R.M., 1977. Herbaceous plants for coastal dune areas. Proceedings of the Florida State Horticultural Society 90: 108-110. 141La Valva, V. & Sabato, S., 1983.Nomenclature and typification of Ipomoea imperati (Convolvulaceae). Taxon 32: 110-114. 151Martinick, W.G. & Atkins, K , 1992. Establishment and management of vegetation on mine waste and land adversely affected by iron ore mining operations in the Pilbara. In: Fox, J.E.D. (Editor): Rehabilitation of mined lands in

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Western Australia. Western Australian Institute of Technology, Bentley, Australia, pp. 69-75. I6l Pongprayoon, U., Bohlin, L. &Wasuwat, S., 1991. Neutralization of toxic effects of different crude jellyfish venoms by an extract of Ipomoea pescaprae (L.) Br. Journal of Ethnopharmacology 35: 65-70. 171van Ooststroom, S.J., 1953. Convolvulaceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana, Series 1, Vol. 4. Noordhoff-Kolff, Djakarta, Indonesia, pp. 458-488. 181 Venkatesan, A., Venkatesalu, V. & Chellapan, K.P., 1995. Photosynthetic characteristics of Ipomoea pescaprae Forsk. under NaCl stress. Photosynthetica 31: 631-634. 191 Wong, P.P., 1978. The herbaceous formation and its geomorphic role in East Malaysia. Malayan Nature Journal 32: 129-141. B. Sunarno &L.P.A. Oyen

K l e i n h o v i a h o s p i t a L. Sp. pi., ed. 2: 1365 (1763).

moderately fine in texture, soft, light, easy to season, work, and finish. Its energy value is about 19 000 kj/kg. The leaves and bark ofK. hospita contain cyanogenic compounds that are assumed to help to kill ectoparasites such as lice. Extracts of the leaves have shown anti-tumour activity against sarcoma in mice. A number of fatty acids with a cyclopropenylic ring (scopoletin, kaempferol, and quercetin) have been isolated from the leaves. Botany Evergreen, bushy tree up to 20 m tall, with a dense rounded crown and upright pink sprays of flowers and fruits. Bole forking low, developing many suckers when old. Bark fissured, greyish outside, yellowish inside. Twigs softly hairy. Leaves simple, alternate; stipules ensiform to linear, about 8 mm long; petiole 2.5-30 cm long; blade ovate to heart-shaped, 5-30 cm x 4-25 cm, glabrous on both sides, apex pointed, secondary veins in 6-8 pairs, palmately nerved. Inflorescence a terminal, loose panicle protruding from the crown; flowers about 5 mm wide, pale pink;

STERCULIACEAE

2n = 20 Vernacular n a m e s Guest tree (En). Indonesia: (ka)timaha, (ka)timanga (Javanese), tangkele (Sundanese). Malaysia: temahai. Papua New Guinea: maroai, matakara, metakek (Bismarck Archipelago). Philippines: tanag (Tagalog), bignon (Ilokano), hamitanago (Bikol). Thailand: chomphu-phuang, hatsakhun-thet, po-farang. Vietnam: tra d[or], c[aa]y tr[af]. Origin and geographic distribution K. hospita occurs naturally throughout tropical Asia, from the Mascarene Islands to Polynesia. It is more common in Central and East Java than in West Java. In Peninsular Malaysia K. hospita is naturally distributed along river banks, especially in Perak and in coastal areas near Melaka. U s e s In the Solomon islands K. hospita provides fuelwood. Its branches which are often twisted, are favoured for ornamental pieces such as knife handles. Straight branches are used for house rafters. Poles are used as stakes for yams (Dioscorea spp.). The fibrous bark is used for rough cordage. The young leaves are eaten as a vegetable. The juice from the leaves makes a good eye wash. In Papua New Guinea and the Solomon Islands a preparation from the cambium is used to treat pneumonia. The leaves are also used as a hair-wash to get rid of lice. The attractiveness of the pink-coloured panicles accounts for its spread as an ornamental. Properties The wood shows a pinkish buff, is

Kleinhovia hospita L. - 1. leaf;2, part of inflorescence; 3, flower; 4, flower with removed sepals and petals; 5,fruiting branch; 6, seed.

KUMMEROWIA

pedicel 2-10 mm long; bracteoles lanceolate, 2-4 mm long, pubescent; gynandrophore 4-7 mm long, pubescent; sepals 5, linear lanceolate, 6-8 mm long, pink, tomentose; petals 5, inconspicuous, upper one yellow; stamens 15, monadelphous, 8-15 mm long, staminal tube broadly campanulate, adnate to gynandrophore, 5-lobed, each lobe with 3 anthers and alternating with staminodes; anthers sessile, extrorse; pistil with a 5-celled, pilose ovary, one style and a capitate, slightly 5-lobed stigma. Fruit a rounded, 5-lobed, membranous capsule, 2-2.5 cm in diameter, loculicidally dehiscent, each locule 1-2-seeded. Seed globose, whitish, warty, exalbuminous. Young trees have a fast growing, deeply penetrating main root and develop an extensive, superficial root system.K. hospita flowers throughout the year. The fruits are more conspicuous than the flowers because oftheir abundance and size. Fruit production starts early, often in the third year after planting. Ecology K. hospita is commonly found in abandoned clearings, grassland and secondary forest from 0-200(-500) m altitude. In Indonesia and Malaysia K. hospita is restricted to areas with a pronounced dry season. In Indonesia it is common in teak forest. In Malaysia it occurs mainly along river banks of the northern part of the Peninsula. It is associated with riverside settlements where it is a vigorous component ofsecondary forest. Agronomy Propagation is by seed. Cuttings are sometimes said to be difficult to root, which is associated with the presence of an uninterrupted sclerenchym band in the pericycle. Other sources report that in the Solomon Islands the bark of the lower part of stakes used in yam plantations is removed to prevent rooting and the development of a shade-producing crown. K. hospita has been tested in alley-cropping systems. It grows well on acid soils and provides a nutrient-rich mulch. Planting material is often easily available from natural stands. Planting in teak forest is not recommended, as it will overgrow the teak trees. The wood is susceptible to drywood termites and powder post beetles. Genetic resources and breeding No germplasm collections and breeding programmes are known to exist. Prospects K. hospita warrants further testing as a reforestation species, as it is common in abandoned clearings and secondary forest. It is also a promising ornamental, similar in habit to Hibiscus tiliaceus L.

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Literature 111Burkill, LH., 1966. A dictionary of the economic products of the Malay Peninsula. 2 volumes. Ministry of Agriculture and Cooperatives, Kuala Lumpur, Malaysia, p. 1302. 2 Corner, E.J.H., 1988. Wayside trees of Malaya. 3rd ed. Vol. 2. The Malaysian Nature Society. United Selangor Press, Kuala Lumpur, Malaysia, p. 708. 131 Henderson, C.P. &Hancock, LR., 1989.A guide to the useful plants of Solomon Islands. Research Department, Ministry of Agriculture and Lands, Honiara, Solomon Islands, pp. 158-160. I4l Kochummen, K.M., 1973. Sterculiaceae. In: Whitmore, T.C. (Editor): Tree Flora of Malaya. A manual for foresters. 2nd ed. Vol. 2. Malayan Forest Records No 26. Longman Malaysia Sendirian Berhad, Kuala Lumpur, Malaysia, pp. 364-365. 151Sultanul Abedin & Abdul Ghafoor, 1976. Sterculiaceae. In: Nasir, E. &Ali, S.I. (Editors): Flora of West Pakistan No 99. Department of Botany, University of Karachi, Karachi, Pakistan, pp. 15-16. A. Latiff

Kummerowia Schindler Feddes. repert. 10:403 (1912). LEGUMINOSAE - PAPILIONOIDEAE

In = 20 (K. stipulacea), 22 (K. striata) Major species and synonyms -Kummerowia stipulacea (Maxim.) Makino, Bot. Mag. (Tokyo) 28: 107 (1914), synonym: Lespedeza stipulacea Maxim. (1859), Microlespedeza stipulacea (Maxim.) Makino (1914). - Kummerowia striata (Thunb. ex Murray) Schindler, Feddes repert. 10: 403 (1912), synonyms: Hedysarum striatum Thunb. ex Murray (1784), Desmodium striatum (Thunb. ex Murray) DC. (1825), Lespedeza striata (Thunb. ex Murray) Hooker &Arnott (1838). Vernacular n a m e s General: kummerowia (En). - K. stipulacea. Korean lespedeza, Korean bushclover, Korean clover (En). - K. striata. Japanese lespedeza, annual lespedeza, common lespedeza (En). Origin and geographic distribution Kummerowia consists of 2 species and both are native to temperate eastern Asia. K. stipulacea is distributed in Japan, Korea, the Amur and Ussuri regions of the Russian Federation, China (except in the southern parts) and central Taiwan. It was introduced into the United States, where it became naturalized in the south-east, particularly in the

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35-40°N area, east of 96°W. K. striata is distributed in Japan, the Amur and Ussuri regions of the Russian Federation, China, northern Taiwan, and Vietnam. It was first reported in the United States in 1846, where it also became naturalized in the south-eastern region, particularly of 3035°N, eastward of 96°W. A taller, more vigorous, late-maturing strain was introduced from Kobe (Japan) into the United States in 1919, which led to a greatly expanded area under Kummerowia. In the early 1950s increasing fertilizer use led to a rapid decline in its importance. Both species are scarcely cultivated outside the United States. Uses Both species produce a thick mat of vegetation providing good ground cover and they are used in the United States for soil conservation and as cover crops.Kummerowia provides good quality forage during summer and is used for grazing and hay. In the United States it is often doublecropped with small cereals harvested for grain or fodder, or is oversown in pastures. Medicinal uses for K. striata have been reported in China. Properties The hay quality of both species is considered to be nearly as good as that of lucerne hay and palatability is excellent. In poor soils their phosphorus and cobalt contents may be lower than required by ruminants. The forage is nonbloating. After flowering starts the feeding value declines, becoming inadequate for dairy cattle. The approximate average composition of hay of K. striata per 100 g dry matter is: crude protein 15 g, fat 3 g, crude fibre 35 g, N-free extract 45 g, ash 5 g, Ca 1 g, P 0.3 g, K 1 g, Mg 0.3 g, Fe 35 mg. The composition ofthe hay ofK. stipulacea is very similar, its ash and mineral nutrient contents being slightly higher. The weight of 1000 seeds is about 1.9g. Description Erect or decumbent, much branched, annual herbs with taproot. Stems slightly pubescent. Leaves alternate, trifoliolate, petiolate, usually small; stipules 2, ovate-lanceolate, large, soft-membranaceous, persistent; stipels absent; leaflets about equal in shape, subentire. Inflorescence an axillary, 1-6 flowered cluster; flowers chasmogamous or cleistogamous, pedicelled; bracts 2, subtending the pedicel; bracteoles 4, persistent, ovate; calyx campanulate, 5-lobed, lobes subequal, pinnately nerved, persistent in fruit; standard suborbicular to oblong, clawed; wings and keel about equal in length; stamens diadelphous; style long, filiform or strongly recurved in cleistogamous flowers. Fruit a unilocular, indéhiscent, 1-seeded pod. - K. stipulacea. Stem erect or semi-erect, coarse,

Kummerowia stipulacea (Maxim.) Makino - 1, habit; 2, leaf with three leaflets; 3, flower; 4, calyx; 5, stamens; 6,pod; 7, seed. strongly and diffusely branched, 10-60 cm long, with upward pointing appressed hairs. Lower leaves spreading, upper leaves folding around developing pod; stipules 4-8 mm long, brown, scarious; petiole 2-5(-10) mm long, glabrate to sparsely antrorse appressed-pubescent; leaflets spatulate to obovate, 0.8-2.5 cm long, 1.5 times as long as wide, base triangular, emarginate, apex mucronulate, glabrous or glabrate, margins conspicuously ciliate. Inflorescence mainly in axil of upper leaves, 1-3-flowered, 1-2 cm long, leafy; bracteoles 1-3-veined; calyx-tube 1 mm long, with obtuse lobes, glabrous; corolla pink to purple, (4.5-)6-7(-10) mm long. Pod ellipsoid, 2.5 mm long, up to halfway covered by the persistent calyx, more commonly borne terminally than along the stems. Seed purplishblack. - K striata. Stem decumbent or erect, slender, branched and wide-spreading, 10-40 cm long, with downward curved, white hairs, often reddish. Stipules 3-6 mm long, striate, brown, pa-

KUMMEROWIA

pery; petiole 2-4 mm long, retrorsely appressedpubescent; leaflets obovate to oblong, 6-15(-20) mm x 2-8 mm, tapered at base, apex obtuse to acute, lateral nerves close and distinctly parallel, inconspicuously appressed-ciliate. Flowers in clusters of (l-)2-6, 5 mm long; bracteoles 5-7veined, not longer than the calyx-tube; calyx 2.5-3.5 mm long, with acute lobes, loosely shortpilose, margins hairy; corolla pink to purple; standard 2 mm x 2 mm; wings white, 3 mm long; keel white, purple-brown-tipped. Pod flat-ellipsoid, 3 mm x 2 mm, minutely hairy and glandular, mottled reddish purple on light brown, covered by the persistent calyx for more than half way. Seed mottled black. Growth and development Hard-seededness reduces germination of both species immediately after harvesting to about 50%; 4 months later the germination rate has increased to 90%. Both species will germinate in early spring in the United States, but usually grow very little until June. Flowering is induced by short daylength. In the United States, plants start flowering in August and mature in October-November. K. striata flowers later and requires a longer growing season than K. stipulacea. Exposure of K. stipulacea to a daylength of less than 13-14 hours inhibits vegetative growth and induces flowering. Therefore, early cultivars are not suitable for planting early in the season in the United States. Other botanical information Both species were formerly classified in the genus Lespedeza Michaux. They have been transferred to their own genus Kummerowia because of the number of bracteoles (4; in Lespedeza there are 2), petals non-persisting in fruit, and their reproductive isolation. Older cultivars of K. stipulacea are 'Climax' and 'Harbin'. The improved cultivars 'Summit' and Tadkin' were released in the 1960s. The most widely grown cultivar ofK. striata is 'Kobe', which is best suited to the southern part of its range in the United States. The more recently released 'Marion' is resistant to bacterial wilt and tar spot, and is better adapted to the northern part of the K. striata area. In New South Wales (Australia), 'Kaloe' was released in 1971. 'Rowan' is fairly nematode-resistant. Ecology Both are warm temperate species, and early frost may kill young plants, whereas mature plants will be killed by the first severe frost in autumn. Both species are fairly drought-resistant. Growth may be severely reduced under dry conditions, but plants recover quickly after rain. The

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mean annual temperature required ranges from 8-26°C. Kummerowia is adapted to a wide range of soil conditions. K. striata does not grow well on wet, poorly drained soils. Optimum pH is 5.5-6.0. K. stipulacea is more sensitive to soil acidity than K. striata. Strain 'Iowa 39' of K. stipulacea can grow in soils ofpH 8. Both species failed in trials in Singapore; they are apparently only suited to higher altitudes in the tropics. Propagation and planting K. stipulacea and K. striata are propagated by seed. They can be oversown in established grassland by broadcasting seed at a rate of 15-20 kg/ha. When sown as a sole crop, 25-35 kg/ha are needed. Sowing may be carried out from winter to early spring in the United States.K. striata reseeds easily because its fruits are formed close to the ground. Husbandry Until the 1950s Kummerowia was most commonly grown in an annual rotation with winter cereals. The initial sowing would be made into the cereal crop during late winter or early spring. The cereal would be harvested for pasture or grain, leaving Kummerowia to be used for summer pasture or hay. About the time Kummerowia was making seed, the field would be ploughed and sown back to cereals. Although adapted to poor soils, both species respond well to fertilizers and lime. K. stipulacea is more responsive to lime than K striata. It is recommended to apply nitrogen and phosphorus fertilizers at sowing or when the crop starts to develop. Nitrogen applications of more than 35 kg/ha will reduce stands in mixtures with grasses. Fertilizing with boron is important when harvesting seed or when reseeding ofthe crop is desired. Natural reseeding in both species results in good stands year after year if competition is not too severe and harvested not too late in the season. Grazing or mowing will stop upward growth, causing lower branches to spread along the ground. Heavy trampling is tolerated and some seed is produced even under heavy grazing. Diseases and pests Both species are considered fairly tolerant to diseases and pests in the United States, but they may nevertheless experience considerable losses. Losses caused by diseases are much greater than those caused by pests. Bacterial wilt (Xanthomonas lespedezae) is serious in the growing area in the United States. Tar spot (Phyllachora lespedezae) causes heavy spotting of leaves, followed by defoliation and reduction in yield and quality. K. stipulacea is more

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susceptible to both diseases t h a n K striata. Several nematodes attack Kummerowia; root-knot nematode (Meloidogyne spp.) may cause serious losses on sandy soils. 'Rowan' is fairly resistant. Grasshoppers may cause defoliation, but only when no other crops are available. Larvae of the crane fly (Tipula simplex), the alfalfa hopper (Stictocephala festina) and the lespedeza webworm (Tetralopha scortealis) occasionally cause damage in the United States. Harvesting If reseeding is desired, plants should be cut early and at more than 10 cm above the ground, to allow adequate regrowth. For hay, the crop should be cut at early bloom to obtain optimal quality. The hay contains less moisture than most other forages and cures quickly. Under optimum conditions, it can be cut in the morning and baled in the afternoon of the same day. When grown for seed, the crop is combine-harvested as soon as it is mature, to reduce losses from shattering. Yield Hay yield ranges from 2500-5000 kg/ha. Average daily weight gains of steers fed with Kummerowia hay is 600-900 g. Seed yield is commonly 200-400 kg/ha, but up to 600 kg/ha can be obtained under favourable conditions. Genetic resources and breeding The number of accessions of both species held by the United States Plant Germplasm System is small (22 ofif. stipulacea and 43 of K. striata) and in need of thorough evaluation. There is a great need for collection of additional germplasm material that could provide breeders with more variability. At present, noKummerowia breeding programme exists. Prospects Kummerowia species are promising as cover and forage crops under subtropical or tropical highland conditions. It would therefore be worthwhile to test both species under these conditions in South-East Asia. No new developments in the United States are expected for either species, unless the cost of nitrogen fertilizers increases and legumes become more economically attractive. Literature 111 Davis, D.K., McGraw, R.L. & Beuselinck, P.R., 1994. Herbage and seed production of annual lespedezas as affected by harvest management. Agronomy Journal 68: 704-706. 121 Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 116-120. I3l Henning, J.C. & Risner, N.E., 1993. Annual lespedeza. Agricultural publication G04515. Department of Agronomy, University of Missouri, Columbia, United States.

141 Henson, R. (Editor), 1957. The lespedezas. Advances in Agronomy 9: 122-141. I5l Hoveland, C.S. & Donelly, E.D., 1985. The lespedezas. In: Heath, M.E., Barnes, R.F. &Metcalfe, D.S. (Editors): Forages. The science of grassland agriculture. 4th Edition. Iowa State University Press, Ames, Iowa, United States, pp. 129-135. 161Offut, M.S., 1986. Some effect of photoperiod on the performance of Korean lespedeza. Crop Science 8: 309-313. J.A. Mosjidis Lespedeza cuneata (Dumont de C o u r s e t ) G. D o n Gen. syst. 2:307(1832). LEGUMINOSAE - PAPILIONOIDEAE

2n = 18, 20 Synonyms Hedysarum sericeum Thunb. ex Murray (1784), Anthyllis cuneata Dumont de Courset (1811),Lespedeza sericea (Thunb. ex Murray) Miquel (1867), non Benth. (1852). Vernacular n a m e s Chinese lespedeza, sericea lespedeza, perennial lespedeza (En). Indonesia: lurampa ghaki. Philippines: lalagim (Igorot). Origin and geographic distribution L. cuneata is indigenous to the Sino-Indian region of Asia and occurs naturally from Japan to Australia and from northern Pakistan and India to Taiwan. In Malesia, it is reported from Java, the Philippines, and Papua New Guinea. Introduced to the United States in 1896, it became naturalized in the south-eastern region. In the United States, it is cultivated eastward of96°W between 30-40°N. Uses In the United States, L. cuneata is one of the most commonly used cover crops for planting on disturbed and eroding areas and on roadsides. In Japan, it is planted in mixtures with other species, also to control erosion of roadsides. It is often the first species planted when rehabilitating strip mine spoils. In the United States, it is grown as a non-bloating forage crop for grazing or hay. L. cuneata also has ornamental value. Properties Fresh forage ofL. cuneata is generally of low palatibility and digestibility. Early work related this to a high tannin and lignin content and thick, coarse stems, but the factors affecting palatibility are not yet fully understood. Finer-stemmed cultivars, some of them also lower in tannin, have been developed. Preservation of forage as hay reduces tannin content and increases intake and digestibility in ruminants. The approximate average composition of hay per 100 g dry matter is: crude protein 15 g, fat 3 g, N-free

LESPEDEZA

extract 48 g, crude fibre 27 g, ash 6 g, P 0.2 g, K 1 g, Ca 1.5 g, Mg 0.2 g, Fe 30 mg, Mn 125 mg, carotene 4 mg, riboflavin 1mg. Whole plants contain 5-8% tannin, leaves 7.5-18%; young plant parts contain less tannin than older ones. The weight of 1000 seeds is 1-2 g. Description A deep rooting, erect, rarely semiprostrate, short-lived perennial herb, 0.5-1 m tall, copiously branched. Stem striate, sparsely appressed-pilose on the ridges. Leaves alternate, trifoliolate; stipules lanceolate, 3-11 mm long, 3veined; petiole 2-7 mm long; rachis 1-2 mm long; leaflets oblong-cuneate to linear-lanceolate, up to 3 cm x 0.5 cm, glabrous above, grey-green or silvery-silky beneath, margins slightly incurved. Inflorescence an axillary, 1-4-flowered fascicle; bracteoles 2; pedicel 1-2 mm long; flowers chasmogamous or cleistogamous; chasmogamous flowers with sericeous calyx, tube 0.5-1 mm long, teeth 5, 3-5 mm long, petals white to cream, standard 6-9 mm long, 1-2 mm longer than keel and wings, purple-veined; cleistogamous flowers com-

Lespedeza cuneata (Dumont de Courset) G. Don 1, flowering branch; 2, leaf; 3, chasmogamous flower; 4, cleistogamous flower; 5,pod; 6, seeds.

171

mon, calyx sericeous, teeth 1.5-2 mm long, olive green to brown, corolla absent. Fruit an ovoid pod, 2.5-3 mm long, glabrous or appressed-pubescent, 1-seeded. Seed ovoid, 1.5-2 mm long, greenish-yellow with brown speckles. Growth and development Seedlings emerge 7-10 days after sowing under optimum conditions of temperature and adequate soil moisture. The optimum temperature for germination is about 30°C; germination percentage is reduced to less than 70% at 15°C and to less than 20% at 10°C in most lines. Growth of seedlings and young plants is slow. In the United States, crown buds appear below ground level toward the end of the season and remain dormant until spring. In spring, new stems arise from those buds as soon as the temperature rises. A late frost may kill the new spring growth, but plants are not severely affected and will regrow. Unlike many other legumes in the United States, L. cuneata will grow actively throughout the summer. In August, shoot growth decreases and nutrient reserves are built up in the taproot for winter storage. Flowering starts in early September. The relatively long growing period contributes to its persistence in plant mixtures. Chasmogamous flowers are pollinated by several species of bees. Other botanical information Species of the genus Lespedeza Michx. are closely related to those of the genera Kummerowia Schindler and Campylotropis Bunge. They have all been included in Lespedeza in the past. However, Kummerowia has now been separated again, as no interspecific crosses have been obtained between species ofLespedeza and Kummerowia. Pods of chasmogamous and cleistogamous flowers can be distinguished; those of chasmogamous flowers have a persistent style, those of cleistogamous flowers are blunt and rounded. Commercial cultivars in the United States can be grouped according to their tannin content. High in tannin are 'Appalow', 'Interstate', 'Interstate 76', 'Serala', and 'Serala 76'. Low in tannin are 'AU Donnelly' and 'AU Lotan'. 'AU Lotan', 'Interstate 76' and 'Serala 76' are tolerant of some nematode species, making them more persistent on light, nematodeinfested soils. 'AU Donelly' is resistant to Rhizoctonia spp. Ecology L. cuneata is adapted to tropical, subtropical and warm temperate areas with mean annual temperatures ranging from 10-29°C. It tolerates drought, high levels of aluminium, and low soil fertility. In the Philippines it occurs on grassy

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slopes, from 1200-2200 m altitude; in Taiwan it is common in open locations (roadsides, waste land, hill sides) up to 3100 m altitude. Daylengths of 13 hours or less are required for L. cuneata to flower. Daylength and temperature also strongly influence the proportion of chasmogamous and cleistogamous flowers produced and the seed produced from them; short daylength and low temperature favour the production of seed from cleistogamous flowers. Although a pH of 5.8-6.5 is recommended, L. cuneata tolerates acid soils, including acid subsoils of pH 4. In high pH (8.0) soils, plants will not survive for more than 2 years. The phosphorus requirements of L. cuneata are low compared to those of other forage species. Propagation a n d planting L. cuneata is propagated by seed. Mature seed is hard and needs to be scarified to germinate. Seed is placed at about 0.5 cm depth by broadcasting. Deep sowing will reduce emergence, but will not affect seedling vigour. Seed rate is 15-20 kg/ha when a herbicide is used, otherwise it should be increased to 20-30 kg/ha. L. cuneata is commonly grown as a sole crop; it is sometimes oversown with annual grasses to increase productivity. In the United States, L. cuneata is sown in early spring as soon as there is no risk ofa severe frost. Husbandry Seedlings are extremely slow to establish and are poor competitors with weeds, so weeding or the application of herbicides is essential for establishment. After the first year and with good management, it is highly competitive with weeds. Stands of L. cuneata are severely reduced when grown on poor soils and cut more than twice per year. However, on fertile soils, up to 3 cuts can be done. It is sensitive to being cut back to less than 4 cm, especially when more than 2 or 3 cuts per year are made. When harvested for hay, plants should be cut when stems are 30-35 cm tall, leaving 8-13 cm stubble. Grazing should begin when plants are 20-25 cm tall to avoid close grazing and stand reduction. Although L. cuneata fixes atmospheric nitrogen, this does not become readily available to companion crops. In the autumn, the above-ground growth becomes woody litter, which decomposes very slowly and accumulates on the soil surface. When fertility of degraded soils has improved sufficiently, L. cuneata can be replaced by more productive crops. Eradication can be achieved by increasing the cutting intensity, followed by light disking and then sowing a fast-growing annual crop. The procedure often has to be repeated the following year.

Diseases and pests L. cuneata does not have any major disease or insect pest problems. Some low-tannin genotypes are highly susceptible to a foliar disease caused by Rhizoctonia sp., but all cultivars released in the United States are resistant or tolerant. Root-knot nematodes can be a pest on light soils. Dodder (Cuscuta campestris Yunck.), a parasitic weed, can be a problem and should be eliminated immediately before it produces seed. Harvesting Forage cut for hay in favourable weather cures rapidly and must be carefully handled to reduce leaf losses. Hay can be baled 1 day after cutting. Yield Hay yields range from 5 - 8 ( - l l ) t/ha in the United States. Steers fed on L. cuneata pastures have achieved an average daily weight gain of 660-800 g. Seed yields average 350-1000 kg/ha. Genetic resources There is a great need to collect germplasm of L. cuneata. The United States Germplasm System holds only 46 accessions, 23 of which are from Japan. Most of the accessions are of limited agronomic potential. Other collections also hold only a few accessions. Breeding A programme to select genotypes tolerant of frequent clipping and to improve the grazing quality of older crops has been started at Auburn University, Alabama, United States. Prospects Its tolerance for poor, acid soils with high aluminium and low phosphorus levels and its persistence in mixed stands make L. cuneata a potentially useful cover crop for tropical highlands. It is one of the best plants for the warmer parts of the United States to rehabilitate seriously degraded land and to grow in low-input systems, because of its adaptation to marginal soils, low fertilizer requirements, high production of organic matter, and ability to fix atmospheric nitrogen. It may be useful in pasture renovation, but more research is needed on its establishment and management in grass sods. Literature 111Dove, D., Wolf, D. & Zipper, C , 1991. Conversion of sericea lespedeza-dominant vegetation to quality forages for livestock use. Powell River Project Series, Publication 460-119. 6 pp. 121 Henson, P.R. (Editor), 1957. The lespedezas. Advances in Agronomy 9: 113-157. I3l Kalburtji, K.L. & Mosjidis, J.A., 1993. Effects of sericea lespedeza root exudates on some perennial grasses. Journal of Range Management 46: 312-315. 141 Kalburtji, K.L. &Mosjidis, J.A., 1993. Effects of sericea lespedeza residues on cool-season grasses. Journal of Range Management 46: 315-319. 151Mkhatshwa, P.D. & Hoveland, C S . ,

LEUCAENA

1991. Sericea lespedeza production on acid soils in Swaziland. Tropical Grasslands 25: 337-341. 161 Mosjidis, C.O'H., Peterson, C.M. & Mosjidis, J.A., 1990. Developmental differences in the location of polyphenols and condensed tannins in the leaves and stems of sericea lespedeza, Lespedeza cuneata. Annals of Botany 65: 355-360. I7l Mosjidis, J.A., 1990. Daylength and temperature effects on emergence and early growth of sericea lespedeza. Agronomy Journal 82: 923-926. I8l Qiu, J., Mosjidis, J.A. & Williams, J.C., 1995. Variability for temperature of germination in sericea lespedeza germplasm. Crop Science 35: 237-241. J.A. Mosjidis

L e u c a e n a diversifolia (Schlecht.) Benth. Hook. J. Bot. 4:417(1842). L E G U M I N O S A E - MlMOSOIDEAE

2n =52 (diploid taxa), 104 (tetraploid taxa) (extra chromosomes are common) S y n o n y m s Acacia diversifolia Schlecht. (1838), Leucaena laxifolia Urban (1900), L. stenocarpa Urban (1900). Vernacular n a m e s Leucaena (En). Indonesia: lamtoro. Philippines: ipil-ipil. Origin and geographic distribution L. diversifolia is of Central American origin, occurring naturally from eastern and central Mexico through Honduras to Nicaragua. It was introduced into Cameroon, Ivory Coast and Java in the late 1800s. It is now widespread throughout the tropics, particularly in South-East Asia. Uses L. diversifolia is primarily used as fuelwood and as a shade tree e.g. in coffee and cocoa plantations in Indonesia and Mexico, and as a green manure. In reforestation schemes, it is planted for soil amelioration and stabilization. In agroforestry and mixed pastures, it is grown as an alternative for L. leucocephala (Lamk) de Wit, where the latter performs poorly because of high altitude or psyllid attack. Sufficiently large logs are used in construction and as poles. Properties The wood of L. diversifolia has a density of 400-500 kg/m3, its energy value is 18 900-19 300 kJ/kg. The leaves have a lower digestibility of crude protein than those of L. leucocephala, but this may not affect the total protein uptake. The mimosine content is low (1.5-2.5%). Rations for ruminants should not contain more than 50%L. diversifolia, and the proportion in rations for non-ruminants should not exceed 10%. L.

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diversifolia produces a water-soluble gum containing the sugar rhamnose. Botany Tree or erect shrub, 3-20 m tall, and with a straight bole up to 40 cm in diameter and slender, ascending branches with horizontal twigs. Bark greyish, lenticellate. Leaves bipinnate, 8-25 cm long, with 12-35 pairs of pinnae and up to 4 large glands between basal pairs of pinnae; petiole and rachis reddish; per pinna 20-60 pairs of leaflets; leaflets linear, 3-6 mm x 1-2 mm, apex acute. Inflorescence a globose, dense head, 6-15 mm in diameter, reddish, borne in clusters in leaf axil, bearing 50-90 flowers; flower light pink to bright red; calyx 1.5 mm long, corolla 3 mm, stamens 10, 4-7 mm long. Pod 10-18 cm x 8-12 mm, bright red, glabrous. Mature seed about 5mm long. L. diversifolia typically grows as a singlestemmed tree with a straight bole and slender upcurving branches. It nodulates and fixes atmospheric nitrogen with Rhizobium strains that also

Leucaena diversifolia (Schlecht.) Benth. - 1, flowering branch; 2, pods.

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nodulate with L. leucocephala. On soils very low in nitrogen, a moderate application of N fertilizer may increase nodulation and nitrogen fixation. A fertilizer application of 50-100 kg N/ha was found to increase the number of nodules per tree from 11.5 to 25-30, while nodule dry weight increased by 63-70%. L. diversifolia is variable in size, adaptation and pubescence, and is subdivided into 2 subspecies: subsp. diversifolia and subsp. stenocarpa (Urban) Zarate (synonym: subsp. trichandra (Zucc.) Pan & Brewbaker). Subsp. diversifolia is tetraploid and occurs wild only in Vera Cruz State in Mexico; it has long leaves, more leaflets per pinna, a longer corolla and pistil, larger pollen grains and larger seed. It is self-compatible, while the diploid subsp. stenocarpa is self-incompatible. Pods of subsp. stenocarpa mature in 80-160 days, those of subsp. diversifolia in about 90 days. Tetraploids are the more commonly cultivated. Cultivars 'K156' and 'K784' developed in Hawaii are commonly used in agroforestry. The widely used cultivar 'KX3' is an interspecific hybrid between L. diversifolia and L. leucocephala. The taxonomy of Leucaena Bentham is still in flux; the currently recognized 17 species hybridize easily, but hybrids are rare in nature. Ecology In the tropics, L. diversifolia grows in areas from 700-2500 m altitude; subsp. diversifolia occurs naturally above 1000 m altitude. L. diversifolia is found in cool and seasonally wet locations with an average annual rainfall of 600-2800 mm and a mean maximum temperature of the hottest month of 18-30°C. It does not withstand drought well. It has a strong light requirement and tolerates only partial shade. L. diversifolia prefers slightly acid, fertile soils, but is tolerant of leached soils. It is often grown in deforested, degraded areas, dominated by Imperata cylindrica (L.) Raeuschel and Themeda triandra Forssk. Agronomy L. diversifolia is propagated by seed. Cuttings and grafts mostly fail, but propagation by tissue culture has been successful. Seed takes about a week to germinate if presoaked in water for 24 hours. The germination rate is generally over 90%. Mechanical scarification and soaking in concentrated sulphuric acid for 5-7 minutes or in hot water (75°C) for 3 minutes also give good results. Seedling vigour is poor, especially in tetraploid and small-seeded diploid forms. Seedlings reach a height of 15-30 cm in 8-12 weeks and are then transplanted into the field. Application of 15 g of a complete NPK fertilizer (14:14:14) per plant may improve the survival rate

of seedlings. L. diversifolia has been tested in intercropping systems e.g. with sweet potato. The total biomass yield of sweet potato, firewood and green manure was considerably greater than the yield per unit area of sweet potato alone. The annual leaf dry matter production ofL. diversifolia can reach 10-16 t/ha. When incorporated as green manure, this adds per ha 72-119 kg N, 2.5-3 kg P, 29-60 kg K, 47-94 kg Ca and 7.5-18.5 kg Mg to the soil. This is equivalent to about 10 t/ha cattle manure per year. Soil erosion can be controlled effectively by planting L. diversifolia. In a trial planting, annual soil loss per ha decreased from 190 t before planting to 54 t in the third year after L. diversifolia had established. The aggressive nature and profuse growth of L. diversifolia occasionally make it a weed. Seedlings can be controlled effectively by spraying them with diesel oil at the 3-5 leaf stage. Established trees can be controlled by impregnating freshly cut stumps of a basal diameter of 1-20 cm with diesel oil. The treatment should be repeated on coppiced stumps. Delaying application until one day after cutting will reduce its efficacy. A common disease is leaf spot caused by Camptomeris leucaena. Spots on the upper leaves are often insignificant, but the fungus sporulates profusely, producing crowded black pustules on lower leaves. Fusarium semitectum causes gummosis and canker on stems, branches and peduncles, dark brown spots on young twigs, leaves, peduncles, pods and seeds, eventually causing the tree to die. A moth, Spatularia mimosae, may cause economically significant damage to seeds. Diploid forms of L. diversifolia have a high psyllid resistance, tetraploid forms are only moderately resistant. Diploids and tetraploids show high resistance to seed beetles, Araecerus levipennis and A. fasciculatus; in Hawaii damage to unprotected seed is often only one-quarter of that to seed of susceptible Leucaena species. There are indications that L. diversifolia is tolerant of some rootattacking nematodes. Genetic resources and breeding Major germplasm collections are maintained by the Nitrogen Fixing Tree Association (Waimanolo, Hawaii, the United States) and at the Australian Tropical Forage Genetic Resource Centre (Brisbane, Australia), and a smaller collection at the Southern Regional Plant Introduction Station (Griffin, Georgia, the United States). L. diversifolia is important in Leucaena breeding programmes, as it is used as one of the sources of resistance to psyllids and of tolerance to low temperature to be incorpo-

LEUCAENA

rated into L. leucocephala. It easily crosses with nearly all Leucaena species, producing viable hybrids. Prospects L. diversifolia is a fast growing, nitrogen-fixing tree, capable of producing high wood and fodder yields and is especially suitable for higher elevations in the tropics. Literature 111Apigo, R.S., Tumaliuan, B.T. & Tagana, R.M., 1987. Leucaena diversifolia: a possible substitute to L. leucocephala. Canopy International 13(5): 1-2. 121 Bray, R.A. & Sorensson, CT., 1992. Leucaena diversifolia - fast growing highland NFT species. NFT Highlights 92-05. Nitrogen Fixing Tree Association (NFTA), Paia, Hawaii, United States. 2 pp. I3l Brewbaker, J.L., 1987. Species in the genus Leucaena. Leucaena Research Reports 7: 6-20. 141 MacDicken, K.G. & Brewbaker, J.L., 1988. Growth rates of 5 tropical leguminous fuelwood species. Journal of Tropical Forest Science 1: 83-91. 151 Pan, F.J., 1988. Comparison of diploid and tetraploid Leucaena diversifolia. Quarterly Journal of Chinese Forestry 21: 89-98. 161 Sorensson, C.T. & Brewbaker, J.L., 1994. Interspecific compatibility among 15 Leucaena species via artificial hybridization. American Journal of Botany 8: 240-247. 171 Zarate, S.P., 1984. Taxonomie revision of the genus Leucaena Benth. from Mexico. Bulletin of the International Group for the Study of the Mimosoideae 12: 24-34. LB. Ipor

L e u c a e n a l e u c o c e p h a l a ( L a m k ) d e Wit Taxon 10:53 (1961). LEGUMINOSAE - MIMOSOIDEAE

2n =104 Synonyms Leucaena glauca (Willd.) Benth. (1842),L. latisiliqua (L.) Gillis (1974). Vernacular n a m e s Leucaena (En). White leadtree (Am). Leucaene, faux mimosa (Fr). Indonesia: lamtoro (Javanese), pelending (Sundanese), petai cina (Indonesian). Malaysia: petai belalang, petai jawa, ipil-ipil. Papua New Guinea: lamandro. Philippines: ipil ipil, elena (Tagalog), palo-maria (Bikol), kariskis (Ilokano). Cambodia: khtum té:hs, krâthum' thé:t. Laos: kathin, kan thin, kh'o:ng ko:ng kha:w. Thailand: krathin (general), to-bao (southern). Vietnam: keo d[aaj]u, bo ch[es]t. Origin and geographic distribution Leucaena evolved in the Guatemalan centre ofgenetic diversity, as a probable tetraploid hybrid of diploid

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species in that region. Two major forms are found. The 'common' shrubby form grows up to 8 m tall and is evidently indigenous to the Yucatan Peninsula. The arboreal 'Salvador' type grows to 16 m and appears to have originated in the regions of El Salvador, Guatemala and Honduras. Both forms were distributed widely throughout Mexico and Central America to northern South America prior to 1500 AD. A single variety of the common form was probably brought by Spanish galleons to the Philippines in the early 1600s, from where it was pantropically distributed in the 19th Century. The Salvador forms are more recent in distribution and are known by names such as 'lamtoro gung' in Indonesia, 'giant ipil-ipil' in the Philippines and 'subabul' in India. Leucaenas are found throughout South-East Asia; on many islands common leucaenas dominate the vegetation on coralline soils. Uses Leucaena is a very versatile multipurpose tree. In South-East Asia it provides fuelwood, shade, fodder, green manure, mulch, posts, food and often combinations of these products. Leucaena is probably the most widely used species in alley cropping, where it is planted in hedges along contours at intervals of 3-10 m with crops in between. Other auxiliary uses include live fences, fire-breaks, shelter-belts, live support for vines such as pepper, vanilla, yam and passion fruit, and shade trees for coffee and cocoa. Selections low in seed production are preferred for these purposes. Throughout the tropics leucaena provides a major nitrogen-fixing component of lowland wasteland, fallow land and forest, where it is often a primary source of fixed nitrogen in the ecosystem. In Indonesia leucaena is often planted in home gardens. A dye has been extracted in Central America from the seeds, pods and bark. Research on extraction methods for this potential dye has been conducted in Indonesia. Foliage is fed to ruminant animals as browse or by cut-and-carry methods and mixed with other green fodders; it is milled as a supplement for poultry feed and pelleted for export. Wood is harvested for fuelwood and used in households and industries such as ceramics; it is also converted into charcoal. Increasing use is made of the wood for posts and props, in chipboard and plywood manufacture, for paper pulp, and for furniture and parquet flooring. In Asia people eat the young green shoots before the leaflets unfold; in the Americas, the green seeds are eaten. In Indonesia the mature seeds are eaten, either raw, cooked or

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mixed with other ingredients, sometimes after fermentation as a substitute for soyabean, or added to coffee after roasting. Young pods are eaten raw or cooked and serve as a minor, but useful protein and vitamin supplement from the home garden. The dried seeds are widely used for ornamentation. Production and international trade Leucaena is a major source of fuelwood and is a primary source of leguminous feed in large regions of Indonesia and the Philippines. Most production is on communal lands or small farms. Attempts to commercialize production on large fuelwood plantations (1000 ha or more) for electricity production in the Philippines have not been a great success. Leucaena leaf meal is milled, pelleted and shipped internationally in a very variable annual volume, largely to Japan and Europe. Demand is estimated to be up to 1 million t/year, far exceeding production, with world prices similar to those for lucerne pellets or hay. Prices of fodder and wood vary widely in Asia. Properties Prunings of leucaena applied as green manure decompose rapidly. In litterbag experiments in Nigeria using dried prunings, about 50% ofthe prunings had decomposed after 20 days and 80% after 40 days. Analyses in Ivory Coast gave a half-life time of 31 days. Chemical analyses of prunings of leucaena grown on alfisols in Nigeria indicated per 100 g dry matter: N 3.3-3.5 g, P 0.09-0.25 g, K 2.5-2.8 g, Ca 1.3-1.6 g, Mg 0.2-0.4 g, lignin 13.4 g, cellulose 21.1 g, hemicellulose 13.5 g, polyphenols 5.0 g and a C/N ratio of 45.5. The average composition of the leaves per 100 g dry matter based on various sources is: N 2.9-4.3 g, P 0.1-0.3 g, K 1.5-2.5g, Ca 0.5-2.2 g,Mg 0.2-0.4 g. Leucaena foliage is noted for its good digestibility and high protein value. Feeding leucaena generally improves the total intake of dry matter and of digestible nutrients. Typical values for 'browse fraction' of foliage include 55-70% digestibility, 3-4% N, 6% ether extract, 6-10% ash, 30-50% Nfree extract (neutral detergent fibre 20%), 1.5-2.5% tannins, 0.8-1.87% Ca and 0.23-0.27% P. However, the Na levels are invariably low: 0.01-0.05%. The seeds and leaves contain galactomannan gums that block protein extraction and possibly protein utilization by animals; they may potentially have useful biomedical properties. Leucaena contains the toxic amino acid mimosine which has antimitotic and depilatory effects on animals. It occurs in high concentrations in the growing tips (8-12%), young leaves (4-6%) and young pods and seeds (4-5%). For this reason leu-

caena leaf cannot safely be included in rations for non-ruminants at a level greater than 5% on a dry matter basis. In ruminants the ingested mimosine is converted to the goitrogenic toxin 3-hydroxy4(lH)-pyridone (DHP) by plant enzymes and rumen bacteria. In most countries, including Indonesia and the Philippines, rumen bacterium (Synergistes jonesii), can completely detoxify mimosine and DHP. Leucaena wood has an exceptionally high density and energy value for a very fast-growing tree and makes excellent firewood and charcoal. The wood has a density of 500-600 kg/m 3 and a moisture content which varies between 30-50% depending on maturity. Energy values (bone-dry) of wood average 19 250 kJ/kg, of charcoal 48 400 kJ/kg. The bark is thin. The wood turns well, matures to a golden-brown colour and is hard enough for flooring. It is perishable outdoors, but accepts preservatives well. It does not resist termites. Pulp yields are high (50-52%), lignin levels low, fibres short (1.1-1.3 mm); paper quality generally is considered excellent. The trees occasionally exude a gum very similar to gum arabic, with similar uses and properties; sterile hybrids, especially L. leucocephala x L. esculenta Benth., exude copiously. The weight of 1000 seeds is about 55 g (arboreal forms) and 35-40 g (common bushy forms). Description Shrub or tree up to 20 m tall, forked when shrubby or after coppicing, with greyish bark and prominent lenticels; branchlets terete, at the top densely grey pubescent. Leaves bipinnate with 3-10 pairs of pinnae, variable in length up to 35 cm, with an orbicular gland (up to 5 mm) below the proximal pair of pinnae; stipules small; pinnae about 10 cm long; leaflets opposite, 5-20 pairs per pinna, linear or linear-oblong, (6-)8-16(-21) mm x l-2(-5) mm, base slightly asymmetrically cuneate, apex acute or short-apiculate, both surfaces glabrous, margins ciliate, lower surface glaucous. Inflorescence consisting of pedunculate glomerules aggregated up to 3 in leaf axils or in terminal raceme; peduncle 2-5 cm long, densely grey pubescent; glomerule 2-5 cm in diameter, white; flowers numerous, in globose heads with a diameter of 2-5 cm, white; calyx tubularcampanulate, about 2.5 mm long, puberulous at apex, teeth triangular, acute; petals spathulate, 4.5-5 mm long, puberulous; stamens 10, free, creamy-white to greenish-white; filaments 8-10 mm long; anthers pilose, dehiscing at dawn; pistil 10 mm long, ovary stipitate, velutinous at apex. Pod membranous, straight, dehiscent, 14-26 cm x

LEUCAENA

Leucaena leucocephala (Lamk) de Wit - flowering and fruiting branch. 1.5-2 cm, pendant, brown at maturity, 15-30seeded. Seeds held obliquely in pod, narrowly ovoid, compressed, 6-10 mm x 3-4.5 mm, brown, obtuse at apex, cuneate at base; aréole oblong, open towards hilum. Growth and development Leucaena establishes fairly slowly, particularly in competition with weeds and when grown on soils which are acid or low in nutrients. It sets pods cyclically every 6-8 months if moisture is sufficient, and this is associated with suppression of vegetative growth during fruiting. Arboreal cultivars have been selected for lower flowering rate. Fruits ripen in 10-15 weeks. The flowers are self-fertile and most seed results from self-pollination (this is not true for related species with 2n = 52 or 2ra = 56). Seeds have a hard seedcoat and survive in the soil for a long time. Seedlings produce a single strong taproot in the first month. Nodulation occurs generally within 2 months in the top 20 cm of soil. Rooting is generally deep, making it a good wind-break and companion tree. Rates of growth usually increase after 3 months, continuing lin-

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early for 3-4 years. Mature trees may reach a stem diameter at breast height of 40 cm. Leucaena coppices well. Coppiced stems sprout 5-15 branches, depending on diameter of the cut surface, and 1-4 stems dominate after a year of regrowth. New stems can grow very rapidly and may reach a height of 10 m in 2 years. Individual leaves persist from 4-6 months. They fold at night or under stress. Other botanical information The common and giant forms of L. leucocephala are distinguished taxonomically as L. leucocephala var. leucocephala (common form, shrubby, less than 5 m tall, small plant parts, pubescent shoot tips, seeding profusely) and L. leucocephala var. glabrata Rose (giant form, arboreal, up to 20 m tall, with large plant parts, glabrous shoots). Intermediate types, combining vigorous growth (up to 10 m tall) and large leaves ofgood fodder quality with extensive, low branching are referred to as the 'Peru' form. The giant or 'glabrata' form gives the highest yields of fodder with infrequent cutting, often outperforming the common form by 100%. The best known cultivars in South-East Asia are 'KB', 'K29', 'K67' and 'K636' (now 'Tarramba') which resulted from research work in Hawaii, and the cultivar 'Cunningham' from Australia. Psyllid-resistant cultivars 'KX2' and 'KX3'are interspecific hybrids and are becoming popular in Asia. Ecology Leucaena is found up to 1000 m elevation, but new hybrids such as 'KX3'greatly extend this range to cooler climates. Leucaena generally requires annual rainfall of 650-1500 mm, but can be found in drier and wetter locations. It thrives under irrigation regimes similar to those used for crops such as maize (i.e. > 1200 mm/year). For optimal growth leucaena requires warm conditions: mean annual temperature ranging from 20-26°C, maximum temperature range of the hottest month 24-32°C and minimum temperature range of the coldest month 16-24°C. Some cultivars of leucaena are sensitive for even light frost, which causes defoliation; others tolerate frost well, provided it is not too severe or too frequent. Severe frost kills all above-ground parts, but belowground parts survive and plants will regrow vigorously. Some hybrids e.g. with L. retusa Benth. are more frost resistant. Growth of leucaena is highly light- and temperature-dependent. Daily dry matter increments in Hawaii ranged from 13.8 kg/ha in winter (average temperature of 21°C and irradiation of 15 MJ/m 2 ) to 26.9 kg/ha in summer (average temperature 26°C and irradiation of 23 MJ/m 2 ).

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Leucaena favours deep, well-drained soils with pH > 5, and has a low tolerance to soluble Al. It performs optimally on calcareous soils, but can be found on saline soils and on alkaline soils up to pH 8. Leucaena is not suited to acid soils with pH(H 2 0) < 4.8 or to waterlogged conditions. Adequate levels of available phosphorus are needed. Propagation and planting Leucaena can be propagated by directly sowing seed or by transplanting seedlings. Seed must be scarified to improve germination, usually by placing it in water at 80°C for 3 minutes followed by removal and then allowing it to cool. Inoculation using peat cultures ofimproved rhizobia strains such as CB3060 (TAL 1145) or CB81 is important for early nodulation and growth. In the absence of peat inoculants the soil from under well-established stands of leucaena can be used as inoculant to promote early establishment. This may also promote early infection by mycorrhiza. It is important not to sow the seed more than 2 cm below the soil surface. Where possible, weeds should be controlled either by slashing or by appropriate chemicals, as early growth is severely reduced by competition. In alley cropping, hedges are planted 4-10 m apart with an intra-row spacing of 0.25-1 m, depending on the pruning regime adopted and the associated crops. Spacing is an effective management tool, as it affects diameter growth more than growth in height. Maximum wood yields in 4-year rotations are obtained with 10 000-20 000 trees/ha. For household fuelwood production leucaena is planted at very high densities of up to 40 000 trees/ha and grown in a 3-year cycle, giving stems with a diameter of about 3.5 cm; for timber and fibre production stands are thinned 2-3 years after planting to 1-2 m x 2 m. For forage, seeds are usually sown in rows 1-5 m apart with a seeding rate of 5-7 kg/ha, using fertilizer where necessary to correct known soil deficiencies. In cut-and-carry systems, closer plant spacing gives higher yields of leucaena. However, in grazed situations the wider row spacings of 2-5 m are more appropriate to enable grass to grow between the rows. Leucaena can also be established by raising seedlings in the nursery in long narrow containers (3 cm x 15 cm) which accommodate the strong taproot without coiling. Transplanting is done when seedlings are 3-5 months old, preferably after a month in the full sun. Barerooted seedlings can be transplanted effectively if shoot and roots are topped. Although weed competition strongly reduces early growth, leucaena is often able to survive because of its ability to toler-

ate some shade, thereby eventually growing above the weed canopy, provided the area is not closely grazed or mown. Husbandry Leucaena is a suitable tree for alley cropping provided adequate moisture is available and soil acidity and Al content are not limiting. In long-term alley-cropping experiments in Nigeria and Zaire with leucaena and maize, maize yields in the alley-cropped plots gradually increased over time, but could not be maintained in the plots receiving only chemical fertilizer or manure. In an experiment in Kenya half of the leucaena prunings could be removed for fodder without a significant reduction in maize yield, provided the manure ofthe animals was returned to the field. Plants in established hedges are pruned to 25-50 cm at the planting of the associated crop. Subsequent pruning intervals of 6 weeks during the cropping season have given good results. Hedges could be maintained under this system even where 2 crops ofmaize were grown per year. In India root pruning using a local plough increased yield of the associated sorghum by about 25%. However, information on how to manage the balance of competition between leucaena and the associated crop is still incomplete. Leucaena has been tested as a live support for yam in a trial in Ivory Coast. In spite of regular pruning it reduced yam tuber yields considerably more than live supports ofFlemingia macrophylla (Willd.) Merrill or Gliricidia sepium (Jacq.) Kunth ex Walp. Its stronger branching, denser shade and denser root system made leucaena more competitive than the other species. For grazing, leucaena can be grown with many grasses. Pangola grass (Digitaria eriantha Steudel), guinea grass (Panicum maximum Jacq.), signal grass (Brachiaria decumbens Stapf) and Sabi grass (Urochloa mosambicensis (Hack.) Dandy) are suitable in the tropics. In the subtropics, Rhodes grass (Chloris gayana Kunth) and setaria (Setaria sphacelata (Schumach.) Stapf & Hubbard ex M.B. Moss) are suitable companion grasses. Leucaena is very palatable and stands can easily be weakened by heavy continuous grazing. Several rotational grazing strategies have been successful, including a simple 2 paddock system of 4 weeks grazing / 4 weeks rest and a 4 paddock system of 2 weeks grazing / 6 weeks rest. The main principle is to move the animals before they graze leucaena regrowth. When adequate leucaena is available, cattle should be capable of weight gains of about 1 kg/head per day provided the Na level in the diet is adequate.

LEUCAENA

Diseases and pests There are few diseases of leucaena. Seedling rots such as Phytophthora drechsleri and Fusarium semitectum attack primarily under waterlogged conditions. The root pathogen Pirex subvenosus causes dieback on heavy textured soils in some areas (e.g. on some irrigation areas in north-western Australia). Until the mid-1980s leucaena was relatively free of serious diseases and pests. However, since then devastating effects of the leucaena psyllid (Heteropsylla cubana), a tiny, jumping plant louse have been experienced in many areas where leucaena is grown. Psyllid damage is rarely seen in leucaena's centre of origin in South and Central America, and damage caused by the psyllid has decreased with time in other areas. Populations ofthis insect fluctuate through the season and can reduce yield by over 50%.Attempts to use predatory and parasitic insects for control have met with varying success. The pest now limits the further development of forage leucaena in some areas. Other leucaena species show resistance to psyllids, and have been used in the breeding of resistant hybrids 'KX1', 'KX2' and 'KX3'. Attacks of soft scale (Cocus longulus) and an associated sooty mould can be serious on plants allowed to grow tall. Seed crops can also suffer yield reduction through larvae of the moth Ithome lassula attacking the inflorescences and young pods. In some areas, notably Central America and more recently in Australia, bruchid beetles can seriously reduce or destroy seed crops. Seedlings can suffer attack from cutworms and termites, but, provided there is an adequate stand density, subsequent production is usually not reduced. Harvesting In alley-cropping systems leucaena is generally cut back to 25-50 cm. Pruning is repeated every 6-8 weeks. In cut-and-carry fodder systems the plants are cut back to 0.5-1.0 m height every 6-8 weeks during the growing season and fed fresh to ruminants. In some ofthe Indonesian islands (particularly Timor), fresh leucaena may form a large part of the diet of tethered animals intended for slaughter. Banana pseudostems are also fed, to provide water. Such a diet is grossly inadequate in Na, and salt supplementation is required for good production. Wood harvest periods range very widely, from 1-8 years, depending on size of desired product and harvesting equipment. Matchets are commonly used in Asia, but handsaws and chainsaws can alsobe used. Yield Yields of green manure and forage vary

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with soil fertility, rainfall, altitude and cutting management, from 1-15 t/ha of dry matter per year. Total yields are reduced by frequent cutting, though leaf yield per day may vary little between cutting intervals of 6, 8 or 12 weeks. Highest yields are obtained under wet tropical lowland conditions on deep well-drained, neutral to alkaline soils. Although leucaena is drought tolerant, yields in the dry season are low unless the plants have access to groundwater or are irrigated. Wood yields compare favourably with the best tropical trees, with annual height increments of 3-5 m and annual wood increments of 20-60 m 3 for the arboreal cultivars. Handling after harvest Fodder is commonly fed fresh or provided as a browse. Sun-drying is practised for leaf pelleting and marketing, often by placing branches over a trellis or on asphalt to allow the leaflets to drop. Wood handling is similar to that ofother fuelwood or pulpwood species. Genetic resources Three major collections are held at the University of Hawaii (Honolulu, United States), the Australian Tropical Forages Genetic Resource Centre (CSIRO, Australia), and the Oxford Forestry Institute (United Kingdom). They comprise all 17 Leucaena species and total 2000 accessions derived largely from expeditions to Mexico, Central and South America. They are identified by K numbers (Hawaii), CPI numbers (Australia) or OFI numbers (United Kingdom). Naturalized populations of leucaena in Asia show limited genetic variation and are not recommended for production as they are outyielded by improved cultivars. Breeding Breeding ofleucaena is in progress at the University of Hawaii and the University of Queensland, Australia, with the key objective of incorporating psyllid resistance and cold-tolerance from other Leucaena species (primarily L. diversifolia Benth. and L. pallida Britton & Rose) into agronomically desirable forms ofL. leucocephala. Prospects Over the last 2 decades leucaena has been one of the most promising multipurpose legumes in South-East Asia. The arrival in 1984 to 1986 of the psyllids curbed the previous enthusiasm, but partial control of the problem now occurs with natural or introduced predators. The prospect of new lines or hybrids more tolerant or resistant to the psyllid has renewed interest in this and related species. Newly-bred cultivars widen the climatic range of leucaena to the highlands and subtropical regions, and some of the new hybrids (e.g. 'KX3') are very cold-tolerant. Improved bole shape ('K636'), psyllid resistance

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('KX1', 'KX2'), low mimosine content ('KX3') and increased vegetative vigour are among other advances in breeding. Improved alley-cropping methods of managing leucaena have been developed in Africa, Indonesia, the Philippines and Central America (Haiti). These are expected to improve crop yields in association with leucaena and aid in the stabilization ofland-use systems and offragile tropical soils. Literature 111 Brewbaker, J.L., 1987. Leucaena: a genus of multipurpose trees for tropical agroforestry. In: Steppler, H.A., Nair, P.K.R. (Editors): Agroforestry; a decade of development. International Council for Research in Agroforestry, Nairobi, Kenya, pp. 289-323. I2l International Development and Research Centre, 1983. Leucaena research in the Asia-Pacific region. Proceedings of Singapore Workshop. Nitrogen Fixing Tree Association (NFTA) & IDRC, Ottawa, Canada. 192 pp. 131 Mureithi, J.G., Tayler, R.S. & Thorpe, W., 1994. The effects of alley cropping with Leucaena leucocephala and of different management practices on the productivity of maize and soil chemical properties in lowland coastal Kenya. Agroforestry Systems 27: 31-51. I4l Oakes, A.J., 1968. Leucaena leucocephala; description, culture, utilization. Advancing Frontiers of Plant Science (India) 10: 1-114. 151Palm, CA., 1995. Contribution of agroforestry trees to nutrient requirements of intercropped plants. Agroforestry Sytems 30: 105-124. 161 Pound, B. &Martinez Cairo, L., 1983. Leucaena, its cultivation and use. Overseas Development Administration, London, United Kingdom. 287 pp. 171 Shannon, D.A. & Vogel, W.O., 1994. The effects of alley cropping and fertilizer application on continuously cropped maize. Tropical Agriculture 71: 163-169. 181 Shelton, H.M., Piggin, C M . & Brewbaker, J.L. (Editors), 1995. Leucaena - opportunities and limitations. Proceedings of a workshop held in Bogor, Indonesia, 24-29 January 1994. ACIAR Proceedings No 57. Australian Centre for International Agricultural Research, Canberra, Australia. 241 pp. 191Sorensson, C T . & Brewbaker, J.L., 1994. Interspecific compatibility among 15 Leucaena species (Leguminosae: Mimosoideae) via artificial hybridizations. American Journal of Botany 81: 240-247. 1101Van den Beldt, R.J. & Brewbaker, J.L. (Editors), 1985. Leucaena wood production and use. Nitrogen Fixing Tree Association (NFTA), Wainamalo, Hawaii, United States. 50 pp. R.J. Jones, J.L. Brewbaker &C T . Sorensson

L u p i n u s L. Sp. pi.: 721 (1753); Gen. pi. ed. 5:322 (1754). LEGUMINOSAE - PAPILIONOIDEAE

x =5 or 6;L. albus: 2n = 30, 40, 48, 50;L. angustifolius: 2n = 40, 48;L. luteus: 2n = 46, 48, 50, 52, 104;L. mutabilis: 2n =42, 48 Major s p e c i e s and s y n o n y m s -Lupinus albus L., Sp. pi.: 721 (1753), synonyms: L. termis Forssk. (1775), L. graecus Boissier & Spruner (1843). -Lupinus angustifolius L., Sp. pi.: 721 (1753), synonyms: L. linifolius Roth (1787), L. reticulars Desv. (1835), L. opsianthus Atabekova & Maissurjan(1969). -Lupinus luteus L., Sp. pi.: 721 (1753), synonym: L. odoratus DC. (1825). -Lupinus mutabilis Sweet, Brit. flow, gard., Ser. 1, 2. t. 130 (1825), synonym: L. cruckshanksii Hooker (1831). Vernacular n a m e s General: Lupin (En, Fr). Lupine (Am). - L. albus: White lupin, Egyptian lupin (En). Lupin blanc (Fr). - L. angustifolius: Blue lupin, narrow leaved lupin (En). Lupin petit bleu, lupin à feuilles étroites (Fr). - L. luteus: European yellow lupin, yellow lupin (En). Lupinjaune (Fr). - L. mutabilis: Andean lupin, South American lupin, pearl lupin (En).Tarwi, chocho (Sp). Origin and geographic distribution The origin of Lupinus is unknown; it is distributed over the Mediterranean region, where it occurs from southern Europe to the highlands of North and East Africa, and the American continent, where it is found in the western parts of North and South America, but not in the Amazon basin. Only 12 species are native to the Old World, including the cultivated species L. albus, L. angustifolius and L. luteus. L. albus originates from the Balkan and the Aegean region, L. angustifolius from southern Europe and L. luteus from the western Mediterranean. L. mutabilis is the main cultivated American species, originating from the Andean mountains. Lupin domestication commenced relatively late: 4000-3000 B C The cultivated species are grown worldwide, from cool temperate to subtropical and tropical areas. U s e s Lupins are cultivated as green manure, for soil improvement and in pastures. Lupin has been used as green manure since ancient times. Ploughing in lupin at the flowering or early fruit-

LupiNus ing stage improves soil fertility. Intensive farming and its associated massive use of mineral fertilizers has largely displaced this practice, however. Lupins, especially L. albus, L. mutabilis, L. arboreus Sims and L. polyphyllus Lindley play a prominent role in erosion control, e.g. in Brazil, Peru, New Zealand and Germany. L. arboreus, the tree lupin, a native of California, is also used to consolidate coastal land and in reclamation of kaolin mine spoils. The dry seed of sweet, alkaloid-free cultivars and de-bittered seed is used as fodder in concentrates, as fish feed and, to a lesser extent, for human nutrition. The alkaloid extracts obtained in industrial de-bittering of lupin seed are used as biostimulants and biological insecticides. The fat content of L. mutabilis is sufficiently high to justify the extraction of edible oil. L. luteus is of greatest interest as a protein-rich forage as it resprouts well from axillary buds and becomes woody later than other species. Flowering lupin makes good hay. Dry plants of bitter lupin, mainly cultivars of L. luteus with shattering pods, are eaten by sheep in arid zones during dry summers. Several lupins are used medicinally. A decoction of the seed of L. albus is reported to increase the sugar tolerance in diabetic patients. Traditionally, seed of L. albus is used for a variety of ailments, e.g. as anthelmintic, carminative, deobstruent, diuretic and pectoral. Burning the seeds is said to drive away gnats. The asparagin-rich seed of L. angustifolius has been used in culture media for the production of tuberculin. Production and international trade About 2 million ha are cultivated with lupins world-wide, of which 60% is mainly for grain production and 40% for forage and green manure. The former Soviet Union (1 million ha) and Poland (285 000 ha), where L. luteus is the main species, account for over 90% of the area cultivated for fodder, while Australia is the leading grain producer with 700000 ha ofL. angustifolius. Australia and Chile are the main exporting countries of lupin grain, while the Korean Republic, the European Union and Japan are the leading importers. In Korea, lupin seed is mainly used in fish feed, in Japan and Indonesia for human consumption. Properties Hay from an immature lupin crop contains per 100 g dry matter: crude protein 32 g, fat 5 g, N-free extract 38 g, crude fibre 20 g, ash 4 g, P 0.45-0.5 g, Ca 0.55-0.6 g, Mg 0.35 g. The most salient feature of lupin grain is its high protein content, ranking among the highest for legumes and ranging from 30-50% (28-38% for L.

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angustifolius). The proteins contain only small amounts of sulphur-containing amino acids. L. mutabilis contains 13-23% fat, L. albus 10-14%, whereas all other cultivated species contain less than 7%. The carbohydrate content is 20-30%. The fibre content is inversely related to the size of the grain: 15-18% for L. luteus, 7-11% for L. mutabilis and only 3-10% for L. albus. The ash content varies from 2.5-5%, with little difference between species. The content of the major elements per 100 g dry matter is: P 0.6 g, K 1.1 g, Ca 0.3 g, Mg 0.2 g, Na 1 g. Lupin seed also contains appreciable amounts of ß-carotene, niacin, thiamine and, especially, choline. Toxins reduce the nutritional value oflupin plants considerably. Toxic and bitter quinolizidine alkaloids are the main obstacle in using the seed and the rest ofthe lupin plant. Lupinine and sparteine are the most toxic components. Hydroxyluparine is another lupin alkaloid. The overall alkaloid content of bitter lupin seed per 100 g dry matter ranges from 0.3 g to over 3 g, while selected sweet cultivars contain 0.05-0.2 g. The alkaloids can be removed by boiling or steeping in water. Industrially, they are separated from lupin flour by solvent extraction. The weight of 1000 seeds is 150-500 g for L. albus, 130-200 g for L. angustifolius, 110-180 g for L. luteus and 120-340 g for L. mutabilis. Description Annual or perennial herbs or shrubs, erect to creeping; habit indefinite; taproot strong, deep. Stem branching to 5th-order laterals, glabrous or pubescent, up to 2 m long. Leaves digitately compound, long-petioled, 5-12 foliolate, heliotrope; stipules adnate to the base of the petiole. Inflorescence a terminal raceme, increasing in size with increasing branching order, 20-30-flowered; calyx bilabiate, divided almost to the base; corolla variously coloured, wings connate at the apex, keel beaked; stamens 10, monadelphous. Fruit a straight, compressed pod, usually constricted between the seeds, dehiscent, 3-12-seeded. Seed variable in shape, size and colour, with sunken hilum. Seedling with epigeal germination. - L. albus. Short-hairy annual, up to 120 cm tall. Leaflets of lower leaves obovate, 25-35 mm x 14-18 mm, those of upper leaves obovatecuneate, 40-50 mm x 10-15 mm, all mucronulate, nearly glabrous above, sparsely villous beneath, dark green; stipules setaceous. Inflorescence 5-10 cm long, sessile; flowers alternate; calyx 8-9 mm long, both lips shallowly dentate; corolla 15-16 mm long, white or blue. Pod 6-10 cm x 11-20 mm, shortly villous, glabrescent, yel-

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low, 4-6-seeded. Seed orbicular-quadrangular, 8-14 mm in diameter, compressed or depressed, smooth, dull, light yellow, sometimes with dark variegation. - L. angustifolius. Short-hairy annual, 20-80 (-150) cm tall. Leaflets linear to linear-spatulate, 10-50 mm x 2-5 mm, glabrous above, sparsely villous beneath; stipules linear-subulate. Inflorescence 10-20 cm long; peduncle 1-3 cm long; flowers alternate; lower calyx lip 6-7 mm long, irregularly 3-dentate to subentire, upper lip about 4 mm long, 2-partite; corolla 11-13 mm long, blue. Pod 5-7 cm x 1-1.3 cm, shortly hirsute, yellow to black, 4-6-seeded. Seed ellipsoid, 7-8 mm long, smooth, dull, yellow-brown, dark brown or grey with yellow spots. - L. luteus. Hairy annual, 25-80 cm tall. Leaflets obovate-oblong, 40-60 mm x 8-12 mm, mucronate, sparsely villous; stipules dimorphic, those of lower leaves subulate, 8 mm long, those of upper leaves linear-obovate, 22-30 mm x 2-4 mm. Inflorescence 5-16 cm long; peduncle 4-12 cm long; flowers verticillate, scented; lower calyx

Lupinus angustifolius L. - 1, flowering branch; 2, flower; 3, calyx; 4,pod; 5, seeds.

lip 10 mm long, shallowly 3-dentate, upper lip 6-7 mm long, 2-partite; corolla 13-16 mm long, bright yellow. Pod 4-5 cm x 1 cm, densely villous, black, 4-6-seeded. Seed orbicular-quadrangular, 6-8 mm x 4.5-6.5 mm, compressed, smooth, dull, black marbled with white, with a white curved line on each side. - L. mutabilis. Erect, glabrous annual, 0.5-2.5 m tall. Stem generally slightly woody, more or less glabrous. Leaf (5-)7-9(-12)-foliolate; leaflets ovate to lanceolate or oblanceolate, about 6 cm long, glabrous, yellowish-green; petiole reddishgreen to dark green. Inflorescence up to 60-flowered; flowers verticillate, fragrant; corolla 1-2 cm long, blue and/or pink and white, with yellowish eye. Pod up to 12 cm long, densely hairy when young, up to 9-seeded, almost indéhiscent. Seed 0.5-1.5 cm in diameter, black, brownish black, white or white with a black or grey halo around the hilum. Growth and development During the vegetative phase, leaf rosettes are formed, their longevity depending on species, cultivar and environmental conditions. Flowering is initiated by the influence of vernalization and photoperiod, with major inter- and intraspecific differences. Lupins from the Old World are quantitative long-day plants, L. luteus being the most daylength-sensitive. L. mutabilis is either a scarcely daylength-sensitive short-day species or a day-neutral species. Flowering is stepwise: inflorescences appear on branches of a given order concomitantly with the flowering of inflorescences on the branches of the immediately preceding order. The length of the flowering period of an inflorescence decreases with increasing branching order. Fertilization is essentially autogamous, but is occasionally allogamous as well in some species and under certain environmental conditions. High temperatures and water stress are decisive in determining the end of flowering. The rate of fruit setting varies with the inflorescence order and usually averages 10-30%. When flowering has ceased, seeds grow rapidly and become ripe virtually simultaneously on all branches. Lupins nodulate with Rhizobium lupini and a crop can accumulate 130-240 kg N/ha. In tests in Australia with L. angustifolius, nodules appeared 4-6 weeks after sowing, while nitrogen-fixation started 2 weeks later. Nitrogen-fixation peaked at the beginning of flowering and remained constant until the beginning of seed filling and the onset of water stress; under optimal conditions it may continue until seed maturity and even leaf drop.

LupiNus Other botanical information Three centres of speciation or origin are distinguished: North and Central America, South America, and the Mediterranean-African region. The number of species in Lupinus is disputed. It was long estimated to be about 200, but recent opinion puts it at about 600 or even higher. The majority of the species occur in the Americas and also the new species are described from there. The 4 major cultivated species are quite variable and many cultivars and cv. groups are distinguished. Well-known cultivars of L. albus are: 'Kiev', 'Multolupa' and 'Ultra'; of L. angustifolius: 'Uniharvest', 'Unicrop' and '111yarrie'. Ecology The mean maximum temperature during the growing season is 15-25°C. Higher temperatures and moisture stress hinder flowering and pod setting. Mediterranean species are coldtolerant (-6 to -9°C) during the vegetative period. On the other hand, L. mutabilis seedlings are cold-sensitive, whereas maturing plants are coldtolerant. For optimal yield, rainfall should be over 350 mm during the growing period. L. luteus has the most modest water requirements (250 mm). Lupins are drought-resistant thanks to their deep roots, but are somewhat sensitive to moisture deficiency during the reproductive period. The best soils for lupin cultivation are well drained, neutral to acid loams. Growth is hampered on clayey and waterlogged soils, while highly calcareous or alkaline soils induce chlorosis and also reduce growth, frequently precluding cultivation. The accepted limiting soil level of CaC0 3 is 3-5 g/100 g for L. albus, 0.5-1 g/100 g for L. angustifolius and 0.5 g/100 g for L. luteus. The limestone tolerance of L. mutabilis is midway between those ofL. albus and L. angustifolius. Some cultivars of L. albus are more tolerant ofsoil salinity than most crops. Propagation and planting Lupins require deep soil preparation in order to facilitate root growth. Sowing is done before or after the first rains in autumn in subtropical and warm-temperate regions and in early spring in cool-temperate regions. Early sowing favours growth. Shallow seeding (1-5 cm deep) is advisable. The recommended plant density per ha for sole cropping is 450000-600 000 for L. angustifolius and L. luteus, 250 000-800 000 for L. albus and 200000-400 000 for L. mutabilis. Lupins are often grown mixed with cereals and other fodder legumes. Inoculation with Rhizobium lupini is necessary prior to sowing in fields where lupins have not been cultivated during the last 4-7 years. Husbandry Cultivated lupins must be weeded,

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as they compete poorly with weeds during early growth. Pre-emergence herbicides are often advised. L. angustifolius and L. albus are mostly treated with simazine. Lupins usually require no N fertilization, but soils containing less than 15 mg P/kg should be supplied with a phosphorus fertilizer at a rate of 30-120 kg P 2 0 5 /ha, while soils containing less than 40 mg K/kg should be fertilized with 50-120 kg K/ha. L. angustifolius is sensitive to magnesium deficiency, which can be corrected by applying 15-30 kg MgS0 4 /ha. Lupins should never be continuously grown on the same soil, but should be grown in rotation with cereals. Lupin green manure gives the best yield of the subsequent crop when ploughed in at the grain filling stage. A green manure crop of L. albus in Parana (Brazil) had an effect equivalent to 80 kg N/ha and increased the yield of a subsequent maize crop by 25%. Even when lupins are grown for grain, they have a positive residual effect on the subsequent crops. In an experiment with L. angustifolius grown for grain in Australia, it yielded 2.5 t/ha, while the 2 following wheat crops yielded 5.4 and 4.7 t/ha, respectively. Three consecutive wheat crops yielded 4.0, 3.9 and 3.9 t/ha. The effect is attributed not only to residual nitrogen but also to a reduction of soil borne diseases. However, long-term use oflupins as green manure may lead to soil acidification. Diseases and pests Lupins are most commonly affected by brown leaf spot (Pleiochaeta setosa) and anthracnose {Colletotrichum gloeosporioides), and, to a somewhat lesser extent, root rot (Fusarium, Pythium, the Rhizoctonia complex). The fungus Phomopsis leptostromiformis is a serious disease, as it produces a mycotoxin that causes lupinosis, a disease lethal to cattle and even more so to sheep; some lines resistant to this fungus are available now. The most widespread and harmful pests of lupins include army worms (Heliothis spp.), which damage buds, flowers and pods. Phorbia platura attacks during germination and emergence, and results in plant losses, while the larvae oîSitona spp. severely damage root nodules. Harvesting The habit oflupins, with their rigid stem and high, non-shattering pods, facilitates mechanical harvesting for seed with a conventional cereal harvester. However, such a harvester may damage the seed, so threshing must be done very gently to avoid cracking. Accordingly, the lowest available drum speed and widest possible concave setting should be used. Yield The average dry matter production of

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lupins as forage or green manure amounts to 5-10 t/ha. L. albus and L. angustifolius grain yields can reach 6 t/ha. The typical average grain yield per ha is 1.5-3 t for L. albus, 1-2.5 t for L. angustifolius, 1.2-2 t for L. luteus and 0.75-2 t for L. mutabilis. Handling after harvest Lupin seed should be stored in a dry and cool place and does not require special storage conditions. Genetic resources Germplasm collections of lupin are maintained at the Western Australia Department of Agriculture, South Perth, Australia; at Campex Semillas Baer, Temuco, Chile; and the Banco de Germoplasma Instituto National de Investigaciones Agraria, Madrid, Spain. Breeding Since ancient times, farmers have selected plants of L. albus and L. mutabilis with non-shattering pods and large white seeds that germinate rapidly. Sweet strains of L. luteus, L. angustifolius and L. albus with a low alkaloid content (0.02-0.05 g/100 g) became available in the first 30 years of the 20th Century. Subsequently, strains ofL. luteus and L. angustifolius with nonshattering pods and permeable seeds were developed. Sweet strains of polygenic heredity were recently obtained in L. mutabilis. The current aims of improvement for the Mediterranean region include complete removal of alkaloids, adaptation to winter and spring sowing, increased resistance to cold and diseases, reduced plant height and branching, higher yield levels, higher seed-protein content with more balanced amino acid composition. Selection in L. cosentinii Guss., L. pilosus L. and L. atlanticus Gladst, is currently being directed for use in soil improvement and forage production in clayey or alkaline soils. Prospects Lupins have great potential for soil improvement, particularly in low rainfall areas with poor acid soils and low phosphate status. They are inexpensive sources of protein for livestock and humans. The wide variation in existing Lupinus species and their great ecological adaptability will allow expansion of growing area for various purposes including soil improvement, seed and forage production. Their use in South-East Asia will remain restricted to highland areas. Lupin development has lately been fostered by the establishment in 1980 of the International Lupin Association (Cordoba, Spain) to promote international cooperation and research on lupins. Literature 111 Borman, B.T. & Gordon, J.C., 1989. Can intensively managed forest ecosystems be self-sufficient in nitrogen? Forest Ecology and

Management 29: 95-103. I2l Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 132-141. 131Ford, R., 1990. The international market for lupins. In: von Baer, D. (Editor): Proceedings of the 6th International Lupin Conference, Temuco-Pucón, Chile, 25-30 November 1990. International Lupin Association, Cordoba, Spain, pp. 142-157. 141 Gladstones, J.S., 1984. Present situation and potential of Mediterranean/ African lupins for crop production. Proceedings of the 3rd International Lupin Conference, La Rochelle, France, 4-8 June 1984. UNIP, Paris, France, pp. 17-37. I5l Gross, R., 1986. Lupins in the Old and New World: a biological cultural coevolution. Proceedings of the 4th International Lupin Conference, Geraldton, Western Australia, August 15-22, 1986. Department of Agriculture, South Perth, Australia, pp. 244-277. 161 Hill, G.D., 1995. Lupins. In: Smartt, J. & Simmonds, N.W. (Editors): Evolution of crop plants. 2nd edition. Longman Scientific and Technical, pp. 277-282. I7l Lopez-Bellido, L. & Fuentes, M. 1986. Lupin crop as an alternative source of protein. Advances in Agronomy 40: 239-295. I8l Planchuelo-Ravelo, A.M., 1984. Taxonomie studies of Lupinus in South America. Proceedings of the 3rd International Lupin Conference, La Rochelle, France, 4-8 June 1984. UNIP, Paris, France, pp. 39-54. I9l Rios R., 1996. Tarwi (Lupinus mutabilis Sweet). In: Meneses, R., Waaijenberg, H. & Piérola, L. (Editors): Las leguminosas en la agricultura Boliviana. Revision de information [Legumes in Bolivian agriculture, a review]. Proyecto Rhizibiologia Bolivia, Cochabamba, Bolivia, pp. 209-226. llOl Roder, W., Kharel, D.R., Gurung, P.R. & Dupka, P., 1993. Pearl lupine (Lupinus mutabilis) as a green manure crop in the highlands of Bhutan. Journal ofSustainable Agriculture 3: 9-20. L. López-Bellido &M. Fuentes

Maesopsis eminii Engler Pflanzenw. Ost-Afr. C:255 (1895). RHAMNACEAE

2« = 18 Synonyms Maesopsis berchemioides (Pierre) A. Chev. (1917). Vernacular n a m e s Umbrella tree, musizi (standard trade name) (En). Musizi (Fr). Indonesia: kayu afrika. Origin and geographic distribution M. eminii occurs naturally between 6°S and 8°N in tropi-

MAESOPSIS

cal Africa along the Gulf of Guinea (incuding Sao Tomé) from Liberia to Angola and through Zaire, southern Sudan and Uganda to Kenya and Tanzania. It was introduced into Java in the 1920s and is cultivated there and in Sumatra and Kalimantan. From Java, it was introduced into Peninsular Malaysia in 1952. Plantations of M. eminii have been established in Africa, India, Indonesia, Malaysia and Fiji, while it has been introduced for testing in Costa Rica, Hawaii, Puerto Rico, the Solomon Islands and Western Samoa. Uses In Africa M. eminii is commonly retained in home gardens for shade, fuel and timber, while the leaves are used as fodder. In Africa and India it is often planted as a shade tree in coffee, tea and cardamom plantations, in Zaire also to shade cocoa trees. Because ofits fast growth, it is widely planted for fuelwood, although its light wood is not an ideal fuel. In Java it is commonly planted for this purpose along roads and field boundaries. Musizi is a good general purpose timber for indoor construction, for joinery, boxes, furniture and millwork, corestock for plywood and particle board. In Uganda, M. eminii is used for enrichment planting. The bark is used for roofing and for medicinal purposes in Africa (a decoction is diuretic and purgative). M. eminii is a common ornamental and shade tree planted along roads. Properties The heartwood is yellowish green when fresh, quickly turning golden to dark brown, the sapwood is white. The heartwood is light with a density of 380-480 kg/m 3 , soft, moderately strong and medium to coarse in texture. It dries fairly rapidly with some warp but little checking. Logs have a tendency to split during felling and storage. Timber is easy to saw and works well with machinery, but is difficult to finish. The grain is interlocked. Wood is attacked by termites and is liable to fungal decay, but is highly absorbent and easily treated with preservatives. The wood of M. eminii yields about 50% screened pulp for paper-making, comparable in tearing strength, tensile strength, and bursting strength to commonly used temperate hardwood species. Analyses of seed from Karnataka, India indicate that the seed of M. eminii contains 40-45% of an edible oil, the main components of which are stearic acid (27%), oleic acid (47%), and linoleic acid (15%). Digestibility of the leaves by livestock is excellent and only slightly reduced by heating. The leaves have a dry matter content of 35% and contain per 100 g dry matter: crude protein 26 g, ether extract 3.6 g, ash 5g, neutral detergent fibre

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20 g, lignin 5.4 g, total phenols 2.4 g, tannin (vanilline-HCl method) 5.6 g, tannin (pepsin precipitation method) 0.9 g. The weight of 1000 seeds is up to 200 g. Description Unarmed, evergreen to deciduous tree, 15-25(-45) m tall with an open, spreading crown. Bole exceptionally straight, cylindrical, up to 15 m tall and 50(-180) cm in diameter; buttresses small or absent; bark pale grey to greybrown or almost white, smooth or with deep, vertical, often twisted furrows; slash red outside, yellow near the wood. Branchlets with patent short hairs. Leaves mostly subopposite, simple, glandular-serrulate; stipules subulate, 2-6 mm long, puberulent, caducous; petiole 6-12 mm long, puberulent to glabrescent; blade ovate-elliptical to oblong-ovate, 7-14 cm x 2.5-6 cm, lustrous above, paler beneath, glabrous except when young, base rounded to subcordate, apex acuminate, margins with rounded teeth 0.3-5 mm long. Inflorescence a many flowered, axillary cyme, 1-5 cm long; peduncle 4-25 mm long; flowers bisexual, 5-merous, yel-

Maesopsis eminii Engler - 1, habit; 2, flowering branch; 3, undersurface leaf; 4, flower; 5, brauchtet with fruit.

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lowish-green; pedicel l-3(-6) mm long; sepals deltoid, 2-6 mm long; petals very strongly concaveconvex, hiding the anthers, not clawed; anthers subsessile; style short, dilated; stigma stellately 10-lobed; style and stigma persistent in fruit. Fruit an obovoid drupe, 20-35 mm x 10-18 mm, turning from green to yellow to purple-black when maturing; mesocarp floury, cream-coloured, endocarp creamy-brown. Growth and development M. eminii grows rapidly at 1-3 m per year in height and 1.5-5.5 cm per year in diameter. In Malaysia, it has reached a height of 20 m in 6 years. It flowers from February to May and from August to September in Peninsular Malaysia. Seeds ripen about 2 months after flowering. They are dispersed by birds (especially hornbills in Africa), bats, rodents and monkeys. M. eminii is remarkably long lived for a pioneer species attaining over 150 years. Other botanical information Maesopsis A. Engler is a monospecific genus, rather isolated in the Rhamnaceae because of the structure of its wood, its number of chromosomes, its protogynous flowers and the morphology ofits ovary and style. M. eminii is sometimes divided into 2 subspecies: subsp. eminii (occurring in East Africa and e.g. in South-East Asia; very large trees with large prominent glandular teeth on the leaves), and subsp. berchemioides (Pierre) N. Halle (occurring from Nigeria to Angola; smaller trees with glandular teeth on the leaves much less prominent, about 1-1.5 mm long). Ecology In Africa, M. eminii occurs in association with many other species from lowland tropical rain forest to savanna, extending into submontane forest up to 1500 m altitude, in Rwanda even up to 1800 m. In Java and Malaysia it is mostly planted in the lowland, but it is more vigorous at 600-900 m altitude. It prefers a mean annual rainfall of at least 1200-1300 mm and tolerates a dry season of up to 2 months. In its habitat the mean annual temperature ranges from 22-27°C, the mean maximum temperature of the hottest month from 26-32°C, the mean minimum temperature ofthe coldest month from 16-24°C. It is very light demanding. M. eminii grows best on deep fertile soils. It tolerates a wide range of soils, from medium to light and from neutral to very acid, but it does not tolerate waterlogging. In Malaysia, good growth was obtained on alluvial and sedimentary, granite-derived soils. It was introduced first in German colonial times in the Usambara mountains in eastern Tanzania,

then again in the 1930s and 1960s and has rapidly invaded submontane rain forest, to become the dominant species there. Propagation and planting M. eminii is mostly propagated by seed obtained from fresh ripe fruit, after the pericarp has been mechanically removed and the seed has been dried for several days. To improve germination, seed may be soaked in water for 1-2 days, or in concentrated (20 N) sulphuric acid for 20 minutes. Fresh seed has yielded over 90% germination, but viability decreases rapidly after 3 months. Germination generally takes 2-6 weeks, but has been reported to require 100-200 days. Direct seeding is feasible. Because of the strong development of the taproot, polybag nurseries are preferred to raised beds. Seedlings attain plantable size after 2-24 months. Potted striplings and stumps have given good results. Seedling survival rates of 57-84% are reported from Malaysia. Husbandry Thinning is required after the 5th year to allow a proper crown/stem ratio to develop. For optimal growth, a density of about 125 trees/ha has been calculated in Malaysia. Established plantations may be coppiced. M. eminii is self-pruning. It has been proposed as an alternative for Paraserianthes falcataria (L.) Nielsen, where the latter is affected by Xystrocera wood borers. Rotations in M. eminii plantations are kept at 30-40 years, since older trees are often wind-thrown. Rotations are about 8 years for fuelwood, poles and pulp production. In plantations M. eminii competes well with weeds but cannot suppress Imperata grass. In agroforestry experiments in Rwanda its growth was not affected by any of the associated crops, but yields of the latter were strongly reduced. Common bean (Phaseolus vulgaris L.) did best, yielding about 60%ofthe unshaded controls. Diseases and pests Poorly growing trees of M. eminii on soils of low fertility or with impeded drainage are prone to canker (in Uganda caused by Fusarium solani). Fungal rot may occur during the often long germination period. A bacterial blight may cause damage on poorly drained sites in Malaysia. It is relatively free of pests in SouthEast Asia, only debarking by squirrels has been reported to cause damage in Malaysia. Yield Average annual increments of 8-20 m 3 /ha are common, but can be as high as 33 m 3 . In Malaysia trees planted from seed from Java and Ghana reached harvestable size after 5-8 years. After 5 years at a density of 850 trees/ha the timber yield was about 175 m 3 /ha; after 9.5 years

MELIA

the density was reduced in 2 thinnings to 125 trees/ha, while the timber yield was about 300 m 3 /ha. Genetic resources and breeding M. eminii appears to be a genetically broad species, reflected e.g. in a significant difference in size between East and West African provenances, the former being much taller. In Malaysia collections of genetic resources are maintained by the Forest Research Institute of Malaysia in four localities in Perak, Kedah and Sarawak. Prospects Because M. eminii can easily be propagated by stumps, requiring little attention after planting and yielding relatively well on poor soils, it may continue to play a role in the reclamation of degraded land and enrichment planting. Given its open crown and long lifespan, M. eminii could also continue to play a role as a shade tree for estate crops. Literature 111 Binggeli, P. & Hamilton, A.C., 1993. Biological invasion by Maesopsis eminii in the East Usambara forests, Tanzania. Opera Botanica 121:229-235. l2l Egli, A.E., 1994. Einfluss ausgewählter Standortsfaktoren in Abhängigkeit von zehn nicht Stickstoff fixierenden Baumarten auf die Ertragsbildung wichtiger Feldfrüchte unter agroforstlichen Anbaubedingungen. Ein Beispiel aus Butare/Rwanda (Ost-Zentralafrika) [The effect of interactions of selected environmental conditions with ten non-nitrogen-fixing species of trees on the development of yield of important field crops grown under agroforestry conditions. An example from Butare/Rwanda (Eastern Central Africa)]. Forstwissenschaftliche Beiträge der Professur Forstpolitik und Forstökonomie 1994/13. Departement für Wald- und Holzforschung, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland. 206 pp. I3l Johnston, M.C., 1972.Rhamnaceae. In: Milne-Redhead, E. & Polhill, R.M. (Editors): Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom, pp. 36-38. 141 Mahyuddin, P., Little, D.A. & Lowry, J.B., 1988. Drying treatment drastically affects feed evaluation and feed quality with certain tropical forage species. Animal Feed Science and Technology 22: 69-78. I5l Palmer, E.R., Gibbs, J.A. & Dutta, A.P., 1983. Pulping characteristics ofhardwood species growing in plantations in Fiji. TPI Report L64. Tropical Products Institute, London, United Kingdom. 43 pp. I6l Sandrasegaran, K., 1966. Optimum planting distances and crop densities of ten exotic species utilizing triangular spacing based on a consideration of crown diame-

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ter to stem diameter relationship. Research Pamphlet No 51. Forest Research Institute, Kepong, Malaysia. 44 pp. 171 Smiet, A.C., 1990. Agroforestry and fuelwood in Java. Environmental Conservation 17: 235-238. 181Widiarti, A. & Alrasjid, H., 1987. Penanaman introduksi jenis pohon kayu bakar di lahan kritis Paseh dan Kadipaten [Introduction offuelwood tree species on degraded lands in Paseh and Kadipaten areas]. Buletin Penelitian Hutan 488: 1-17. H.G. Schabel &A. Latiff

M e l i a a z e d a r a c h L. Sp.pl.: 384 (1753). MELIACEAE

2n = 28 Synonyms Melia sempervirens (L.) Sw. (1788), M. dubia Cavanilles (1789), M. composita Willd. (1799). Vernacular n a m e s Chinaberry, Persian lilac, pride of India (En). Indonesia: gringging, mindi (Java), marambung (Sumatra). Malaysia: mindi kecil. Philippines: paraiso, balagango (Tagalog), bagalunga (Bisaya). Singapore: mindi kechil. Cambodia: dâk' hiën, sdau khmaôch. Laos: h'ienx, kadau s'a:ngz. Thailand: lian, lian-baiyai (central), khian (northern). Vietnam: c[aa]y xoan, xoan d[aa]u, s[aaf]u d[oo]ng. Origin and geographic distribution M. azedarach is a widely distributed tree, probably of South Asian origin, occurring widely in tropical, subtropical and warm temperate regions. It is found wild in the Himalayan foothills of India and Pakistan at altitudes of 700-1000 m, widely scattered in China, through Malesia to the Solomon Islands and northern and eastern Australia. It is naturalized in a wide belt in the cooler parts of eastern and southern Africa, in the Americas from Argentina to the southern United States and Hawaii, and throughout the Middle East and the Mediterranean as far north as Croatia and southern France. The most frost-tolerant cultivars can be planted outdoors in sheltered areas in the British Isles. Uses In South-East Asia, M. azedarach is primarily used for fuelwood (e.g. in the Philippines) and is also planted as a shade tree in coffee and abaca (Musa textilis Née) plantations and as an avenue tree. It is a well-known ornamental grown for its scented flowers and shade. In South Asia, M. azedarach is better known for its medicinal uses. Its various parts have anthelmintic, anti-

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malarial, cathartic, emetic, and emmenagogic properties, and are also used to treat skin diseases. The fruits are so highly valued for their medicinal properties in Malaysia that they are imported from Szechuan (China). However, some toxic components occur in the seed oil, the oral intake of which may cause severe reactions and even death. M. azedarach oil may be mistaken for neem seed oil, which is taken orally for medicinal purposes. Aqueous and alcoholic extracts of leaves and seed reportedly control many insect, mite, and nematode pests. However, because they contain toxic components, care is needed in their use. M. azedarach wood (the 'white cedar' of commerce) is also used to manufacture agricultural implements, carts, tool handles, and furniture, and in construction, because ofits termite resistance. Production and international trade Currently, the use ofM. azedarach products is almost entirely restricted to the informal sector. Properties M. azedarach contains numerous compounds with anti-feedant and growth-disrupting properties in insects. These compounds are related to those in neem (Azadirachta indica A.H.L. Jussieu), but recent information indicates that azadirachtin, the most important compound in neem, is absent in M. azedarach. The fruits of M. azedarach are highly toxic to warm-blooded animals; the consumption of 6-8 fruits can cause nausea, spasms and death in children. The proximate oral lethal dose for pigs of purified ethanolic extract of fruits was found to be 6.4 mg/kg live weight. Ruminants seem less sensitive and several species of birds eat the fruits. After eating too many fruits, however, these animals sometimes show mild intoxication and temporary paralysis. The leaves are generally much less toxic and in India are fed to goats. They were also used to rid goats and sheep ofintestinal worms. The presence of toxic and non-toxic forms is reported from New South Wales. The flowers may cause discomfort to asthma patients and the wood dust sometimes induces dermatitis. The bark exudes a water-soluble gum. Of the many compounds isolated from the fruit, the triterpenoid melianotriol, desacetylochinolide B, and several nimbolins and sendanins have shown very strong anti-feedant properties in insects. Insecticidal properties are found in the derivatives of vilasinine, meliacin and meliacarpin. The latter are azadirachtin analogues. Many of these compounds are similar to the insect hormones known as ecdysones, which control moult-

ing and metamorphosis. Toosendanin, a triterpenoid related to sendanin has been isolated from the bark and has nematicidal properties. A glycopeptide in the leaves and roots inhibits in vitro replication of several RNA and DNA viruses. The seed contains an oil high in linoleic acid (65-82%) and oleic acid. The wood ofM. azedarach resembles mahogany. It makes good construction timber, durable even in exposed locations and not affected by termites. Its density is 510-660 kg/m3, its energy value 24 000-25 000 kJ/kg. The weight of 1000 seeds is 75-250 g. Description Deciduous tree up to 45 m tall; bole fluted below when old, up to 60(-120) cm in diameter. Bark grey-brown, smooth, lenticellate, becoming lightly fissured or scaly with age; inner bark yellowish; sapwood whitish, heartwood rusty brown. Crown widely spreading, with sparsely branched limbs. Twigs upturned at end of drooping branchlets, smooth, brown, lenticellate, with raised cicatrices; leafy twigs with fulvous stellate

Melia azedarach L. - 1, habit; 2, leaf; 3, flowering branch; 4, section through flower; 5, infructes-

MELIA

hairs. Leaves bipinnate, occasionally wholly or partly tripinnate, more or less opposite, (15-)2380 cm long, glabrescent; petiole 8-30 cm long, terete, lenticellate, swollen at base; pinnae in 3-7 pairs, up to 25 cm long; petiolule 3-7 mm long; leaflets in 3-7 pairs, opposite or nearly so, ovate or oblong-lanceolate to elliptical, 2-10 cm x 0.6-3.8 cm, base slightly unequilateral, acute to rounded, apex acuminate, margin entire to variously serrate. Inflorescence a thyrse, axillary or in axil of rudimentary leaves on short shoots, 10-22 cm long, primary branches 5-7.5 cm long, secondary branches up to 2 cm long, bearing fascicles of flowers; bracts 3-10 mm long, filiform, caducous, bracteoles similar but smaller; pedicel 2-3 mm long; flowers purplish, fragrant, bisexual or male, 5-merous; calyx tubular, about 2 mm in diameter, lobes about 2 mm long, exterior stellate and with simple hairs; petals free, narrowly oblong, 6-10 mm x 2 mm, white to lilac or bluish, outside minutely pubescent; staminal tube about 7 mm long, lilac turning deep purple, exterior glabrous, interior with dense simple hairs; anthers 10, sessile; pistil glabrous, stigma clavate, 5-lobed. Fruit a drupe, ellipsoid-globose, 2-4 cm x 1-2 cm, yellow-brown when ripe, glabrous, up to 5-seeded. Seed oblongoid, 3.5 mm x 1.6 mm, smooth, brown. Growth and development Under optimal conditions M. azedarach grows fast. In Uganda it has grown about 1.7 m in height annually for several years after planting. It is generally deciduous, but some forms in the humid tropics (e.g. in Malaysia and Tonga) are evergreen. It flowers from March to May in the northern hemisphere, though some forms flower throughout the summer and even throughout the year. Fruit drop is limited and ripe fruits cling to the branches for several months even when leaves have fallen. The tree resprouts after cutting and regrows after pollarding, making it suitable for pole production. Other botanical information M. azedarach is a variable, complex species, comprising many wild and cultivated forms formerly often recognized as separate forms, varieties or species. Besides the wild trees, two groups of cultivars are recognized: Chinese and Indian. The wild tree is taller (up to 45 m), its leaflets are entire, its flowers are sweetly scented to malodorous, the petals white or pale mauve and the fruits up to 4 cm long. It is sometimes grown for wood (e.g. in the Philippines). The Chinese cultivars are smaller, with entire leaflets, fragrant, mauve, pink or blue flowers and larger fruits than the Indian cultivars. In South-East Asia, trees of Chinese cultivars are rare. The Indi-

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an cultivars are more common in South-East Asia; they are smaller trees, with irregularly serrate leaflets and sweet, fragrant, pink or blue flowers. Well-known cultivars in the Indian group are 'Floribunda', a precocious form, flowering when only a few m tall and used as bedding plants, and 'Umbraculifera', a mutant found in Texas with a flattened crown. M. azedarach L. var. australasica (Juss.) DC. which occurs naturally in eastern Australia and is planted in the Philippines, grows into a large tree, to 45 m tall and 1.2 m in diameter under humid conditions. M. azedarach is often confused with the neem tree (Azadirachta indica). Neem can easily be distinguished: it never has stellate hairs, it has pinnate leaves (not bipinnate), 3-lobed stigmas (not 5lobed), and l(-2)-seeded drupes (not up to 5-seeded). Ecology The natural habitat ofM. azedarach is seasonal forest, including bamboo thickets, Tamarindus woodland and Eucalyptus savanna. Its natural occurrence from the Himalayan foothills of Baluchistan (Pakistan) and Kashmir (India) to the lowland of Papua New Guinea indicates that it is highly adaptable and tolerates a wide range of conditions. The mean maximum temperature of the hottest month may reach 39°C, the mean minimum temperature of the coldest month -5°C, although many forms tolerate a narrower range only. In eastern coastal Australia M. azedarach occurs where the mean maximum temperature of the hottest month is 26-32°C and the mean minimum temperature of the coldest month 3-10°C. Young trees are sensitive to frost, but old ones tolerate up to -15°C. It is generally found from 0-1200 m altitude, in the Himalayas up to 1800(-2200) m. Annual rainfall in its natural habitat ranges from 600-2000 mm. In Africa it is planted as a drought-tolerant shade tree and ornamental. M. azedarach is widely distributed in the drier parts of the southern and south-western United States, while in humid Florida it is selfsowing and considered a weed. Where annual rainfall is less than 600 mm, as in parts of the Middle East, it performs well on wet soils along rivers and under irrigation. M. azedarach tolerates seasonal waterlogging and is even reported from permanently waterlogged sites. Strong winds may break off limbs. Although optimal growth is obtained on welldrained, deep, sandy loams, M. azedarach tolerates shallow soils, saline and strongly alkaline soils, but not very acid soils. Reports on its tolerance of heavy clays are contradictory. It is found

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on poor, marginal, sloping, and stony land, even in crevices in sheer rock. Propagation Although successful vegetative propagation through stem cuttings, root suckers and air layering has been reported, propagation is usually by seed. Drupes need to be macerated until the seed can be gently eased out. Seeds are soaked in water for 1-2 days, depulped, and dried in the shade. They can be stored in a cool and well-ventilated place, in cloth or gunny bags. Plastic and other airtight containers should not be used for seed storage. Seed should be planted within two weeks after harvesting, as viability drops rapidly thereafter. Sowing is mostly done in a nursery at 15 cm x 2.5 cm in a sunny place, keeping the seed lightly covered with soil or mulch. Seedlings may be thinned to 15 cm x 15 cm when 2 months old, and transplanted when 7-10 cm tall. Husbandry A few weedings are required during the first 2 years after planting. When grown for timber, stems are pruned to a height of about 6 m to obtain a branch-free bole. In Paraguay, M. azedarach grown in small woodlots for timber, is often interplanted with a variety of food crops. It is planted at a spacing of 4 m x 3 m, thinned after 3 years to 400 trees/ha and after 6 years to 200 trees/ha. Diseases and pests Although some bacterial and fungal diseases have been observed on leaves, twigs, and fruits, no serious damage has been reported. Generally, M. azedarach is also little affected by pests. Harvesting Pollarding ofM. azedarach for fuelwood and poles is usually done on 5-10-year-old trees. Yield In Thailand, timber yields of 10-year-old stands of M. azedarach are estimated to be about 85 t/ha. In Paraguay, 12-15 years after planting, woodlots yield about 100 m 3 posts and small-sized wood and 175 m 3 logs. Under natural conditions, M. azedarach fruit yield is higher than neem's, but there are no data on this. Handling after harvest Fruits should be depulped immediately after collection, and the seed dried in the shade and stored in a well-ventilated, cool place. Genetic resources and breeding No substantial germplasm collections of M. azedarach are known to exist. Neither are any breeding programmes known. Breeding work may lead to e.g. improved burning quality, drought tolerance, and higher fruit and oil yields. Prospects Its quick growth and small dimen-

sions make M. azedarach a good choice for fuelwood production for household needs. Its ability to grow under suboptimal conditions makes M. azedarach suitable for reforestation and reclamation of marginal land in semi-arid areas in tropical highland and temperate regions. M. azedarach may provide excellent prospects for exploitation as a natural pesticide. Literature 111Ahmed, S., Grainge, M., Hylin, J.W., Mitchell, W.C. & Litsinger, J.A., 1984. Some promising plant species for use as pest control agents under traditional farming systems. In: Schmutterer, H. & Ascher, K.R.S. (Editors): Proceedings of the Second International Neem Conference. Deutsche Gesellschaft fur Technische Zusammenarbeit (GTZ), Eschborn, Germany, pp. 565-580. 121Arora, R.K., 1993. Genetic diversity and ethnobotany. In: Randhawa, N.S. & Parmar, B.S. (Editors): Neem research and development. Indian Society of Pesticides Science, New Delhi, India, pp. 33-37. I3l Ascher, K.R.S., Schmutterer, H., Zebitz, C.P.W. & Naqvi, S.N.H., 1995. The Persian lilac or Chinaberry tree: Melia azedarach L. In: Schmutterer, H., Ermel, K., Isman, M.B. & Jacobson, M. (Editors): The neem tree: Azadirachta indica A. Juss. and other meliaceous plants: sources of unique natural products for integrated pest management, medicine, industry and other purposes. VCH Publishers, Weinheim, Germany, pp. 605-642. 141 Dogra, P.D. & Thapliyal, R.C., 1993. Gene resources and breeding potential. In: Randhawa, N.S. & Parmar, B.S. (Editors): Neem research and development. Indian Society of Pesticides Science, New Delhi, India, pp. 27-32. 151 Mabberley, D.J., Pannell, C M . & Sing, A.M., 1995. Meliaceae. In: Kalkman, C , et al. (Editors): Flora Malesiana. Series 1, Vol. 12(1). Foundation Flora Malesiana, Leiden, the Netherlands, pp. 341-343. 161 Nair, M.N.B., 1991.Wood anatomy of some members ofthe Meliaceae. Phytomorphology 41: 1-2, 63-76. 171 Nasayo, E.E., Nasayo, L.Z., Zara, M.A. &Ulep, E.V., 1992. Balunga: Melia dubia Cav.: towering with purposes. Canopy International 18(5): 9-12. 181 Ram, H.Y.M. & Nair, M.N.B., 1993. Botany. In: Randhawa, N.S. & Parmar, B.S. (Editors): Neem research and development. Indian Society of Pesticides Science, New Delhi, India, pp. 6-26. S.Ahmed &Salma Idris

MELILOTUS

Melilotus Miller Gard. Diet., abr. ed. 4 (1754). LEGUMINOSAE - PAPILIONOIDEAE

x = 8;M. alba: In =16, 24, 32;M. indica: 2n =16; M. officinalis: 2« = 16,32;M. suaveolens: 2n = 16 Major species and synonyms - Melilotus alba Medikus, Vorlesungen Churpfälz. Phys.-Ökon. Ges. 2: 382 (1787), synonyms: M. alba Desr. (1796), Trifolium vulgare Hayne (1807). -Melilotus indica (L.) All, Fl. Pedem. 1: 308 (1785), synonyms: Trifolium melilotus-indica L. (1753),Melilotus paruiflora Desf. (1799). - Melilotus officinalis (L.) Pallas, Reise russischen Reichs 3: 537 (1776), synonyms: Trifolium melilotus-officinalis L. (1753), Melilotus officinalis (L.) Lamk (1778). -Melilotus suaveolens Ledeb., Ind. Sem. Hort. Dorpat, suppl. 2: 5 (1824), synonym: M. graveolens Bunge (1833). Vernacular n a m e s General: sweetclover (En). Mélilot (Fr). - M. alba: White sweetclover, white melilot, bokhara clover (En). Mélilot blanc (Fr). -M. indica: Sourclover, Indian clover, senji (India) (En). - M. officinalis: Yellow sweetclover, yellow melilot (En). Mélilot officinal (Fr). - M. suaveolens: Daghestan sweetclover (En). Vietnam: nh[ax]n h[uw][ow]ng. Origin and geographic distribution Sweetclovers are widely distributed throughout Europe and Asia, mainly in temperate and subtropical areas, extending into North Africa, India (M. indica), Indo-China and Taiwan (M. suaveolens). M. alba and M. officinalis are cultivated extensively in North America, where they have attained their greatest importance in the Corn Belt and Great Plains of the United States and Canada, and in Eastern Europe and the Russian Federation. They have been introduced into Australia, South America and into eastern and southern Africa. M. indica is cultivated in India (mainly in the northern parts), in Pakistan and the United States. M. suaveolens is occasionally cultivated in China and North America. U s e s Sweetclover is used for green manure, soil improvement and forage. It is said to have no equal as a soil-improving crop in the United States. As a forage crop, the use of sweetclover as a pasture crop far exceeds its uses for either hay or silage. Good quality hay can be made from the first-year growth. Because hay from the second-

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year growth is rather coarse, forage is often converted into silage. M. suaveolens is grown as a cover crop and forage plant on saline soils in China. Seed oil is used in paint and varnish, and seed meal as protein supplement in cattle feed. Sweetclover is prized as a good honey plant, yielding large quantities of good quality, pale honey with a mild flavour. The honey has been used since the ancient Greeks for flavouring foods and for medicinal purposes, having astringent and narcotic properties. In Vietnam, M. suaveolens is used in lotions to treat eye diseases. Properties The composition of M. alba green fodder per 100 g is: moisture 79.2 g, protein 4.1 g, crude fibre 4-9 g, total digestible nutrients 12.8 g. Chemical analysis of green material showed per 100 g: N 0.83 g, P 0.07 g, K 0.67 g, and Ca 0.50 g. The silage is similar to maize silage in nutritive value, but is not as palatable, containing per 100 g: moisture 72 g, protein 4.5 g, crude fibre 9.6 g, total digestible nutrients 15.7 g. Good quality M. alba hay can approach the chemical composition and feeding value of lucerne hay, containing per 100 g: moisture 8.2 g, protein 16.5 g, crude fibre 24.6 g, total digestible nutrients 50.3 g. Sweetclover contains coumarin, hydrocyanic acid, malonic acid, and melilotin. Coumarin reduces the palatability to livestock. Feeding spoiled hay or silage from high-coumarin cultivars may lead to 'sweetclover bleeding disease'. Affected animals may bleed to death from small wounds or internal haemorrhages. The weight of 1000 seeds is 150-200(-390) g. Description Annual or biennial, sometimes scented herbs. Leaves trifoliolate; stipules adnate to the petiole, subulate; leaflets dentate. Inflorescence an axillary raceme; flowers small; bracts small; bracteoles absent; calyx campanulate with 5 subequal teeth; corolla yellow or white, rarely purple, glabrous, caducous, standard usually longer than keel and wings, keel shorter than wings, obtuse, not adnate to stamens; stamens diadelphous, anthers uniform. Fruit a small pod, straight, ovoid to nearly globose, with persistent pedicel and calyx, 1-4-seeded. Seed smooth or nearly so. - M. alba. Erect, ascending or decumbent, sparsely branched, scented, annual herb, up to 1.5(-2.5) m tall, with long taproot. Stipules lanceolate to setaceous, 4-6 mm long; petiole 0.5-2 cm long, petiolule up to 5 mm; leaflets obovate to oblong-obovate, 1-2.5 cm x 5-12 mm, serrate-dentate almost to the base. Raceme 5-20 cm long, on an up to 4 cm long peduncle; flowers

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mm; leaflets obovate to oblong-lanceolate, 1-2.5 cm x 4-15 mm. Raceme up to 10 cm long, peduncle about 2 cm long; flowers 4.5-8(-10) mm long; calyx teeth equal, acute; corolla yellow; style 1.7-2.3 mm long. Pod ovoid, 3-6 mm long, glabrous, brown when ripe, transversely reticulate or irregularly rugose, usually 1-seeded. Seed ovoid, about 2 mm long, yellow-green. - M. suaveolens. Annual to biennial herb, up to 1.5 m tall, pubescent to subglabrous, with thickened roots. Stem erect, angular, glabrous. Stipules 8-10 mm long; petiole up to 2 cm long, petiolule up to 1 mm; leaflets narrowly elliptical to obovate, 1-3 cm x 3-8 mm. Raceme 10-15 cm long, densely flowered, elongate after anthesis; peduncle 2-5 cm long; flowers pale yellow, 3-4 mm long; style 1.7-2.3 mm long. Pod ellipsoid, about 3 mm long, finely reticulate. Seed ellipsoid, 2 mm long, reddish.

Melilotus alba Medikus - 1, flowering branch; 2, stipules; 3, flower; 4, stamens and pistil; 5, pistil; 6,pod; 7,seed. white, calyx about 2 mm long, corolla 4-6 mm long, style 1.7-2.3 mm long. Pod obovoid to ovoid, 4 mm long, reticulately veined, greyish to blackish-brown when ripe. Seed ovoid, about 2 mm long, yellow-brown. - M. indica. Erect, annual herb up to 60 cm tall. Stem pubescent. Stipules lanceolate to setaceous, 5-8 mm long; petiole up to 4.5 cm long, petiolule up to 5 mm; leaflets oblong to obovate, 0.8-2.5 cm x 2-9 mm. Raceme 10-16-flowered; peduncle up to 3 cm long; flowers yellow; calyx about 1.5 mm long, teeth triangular-lanceolate; corolla 2-3 mm long; style 0.9-1.2 mm long. Pod 1-seeded, 1.5-4 mm long, prominently reticulately veined, olive-green. Seed ovoid, about 2 mm long, yellow-brown, finely verrucose. - M. officinalis. An erect, much branched, scented annual or biennial with stout stem up to 1.5(-3) m tall and thickened roots. Stipules 3-6 mm long; petiole up to 3 cm long, petiolule up to 6

Growth and development Well-ripened, mature seed is hard. Seed can be stored for long periods. After storage for 40 years in stoppered glass bottles, 60% of the seed still germinated in a trial in the United States. During the first year, biennial cultivars form a primary stem which becomes much branched under favourable conditions, a deeply penetrating taproot and, as the season progresses, a crown. When sweetclover is cut early, regrowth is from buds higher up the stem. Top growth reaches maximum development during late summer when a rapid increase in the size of the taproot begins which continues during autumn. Growth in the second year starts quickly and largely consists of rather coarse stems, which may reach to nearly 3 m in M. officinalis. Root thickening does not occur in annual cultivars. Control of flowering and taproot thickening is not fully understood. The flowering of biennial cultivars is initiated by long days. Under a daylength of 18hours, flowering starts within 3 months after sowing. Vernalization seems to be of only minor importance. Sweetclover fixes atmospheric nitrogen and is an aggressive colonizer, quickly invading roadsides, railways and fence lines. Around 1900 it was listed as a noxious weed, but by 1910 its value as a cover crop and green manure plant was well established in North America. Pollination is by insects, mostly honey bees. Flowers of M. alba and M. officinalis only set seed when tripped by visiting insects. M. alba and M. indica are self-fertile; self-incompatibility is common in M. officinalis. Other botanical information Melilotus com-

MELILOTUS

prises about 25 species found chiefly in the Mediterranean region and central Asia. The following characteristics may be useful to easily distinguish between the 4 species described here: M. indica: style length 0.9-1.2 mm (other species 1.7-2.3 mm);M. alba: flowers white (other species yellow); M. officinalis: pod strongly transversely veined (other species irregularly veined); M. suaveolens: style 1.7-2.3 mm long, flowers yellow, pod irregularly veined, plant very fragrant. M. alba and M. officinalis are closely related and sometimes hybridize naturally. Some authors prefer to write M. albus and M. indicus instead of M. alba andM. indica. Well-known annual cultivars of M. alba are 'Emerald', 'Floranna', 'Hubam' and 'Israel'. Biennial cultivars are 'Arctic', an early maturing, winter-hardy cultivar, 'Polara', which is low in coumarin, but produces lower yields, both from Canada, "Denta', from the United States, which is low in coumarin and late, 'Chermasan' and 'Medet' from Russia. 'Goldtop', 'Madrid' and 'Norgold' are cultivars ofM. officinalis commonly used in North America, 'Katek' and 'Omskii Skorospelyi' are used in the Russian Federation. Ecology Sweetclover is adapted to a wide range of climatic and soil conditions. It occurs in grassland, arable fields, wasteland and along roadsides, especially in calcareous soils. It is frosthardy and grows well from sea level up to 2000 m altitude in the United States and China. Sweetclover is drought tolerant, requiring enough moisture for germination, after which it will survive under dry conditions. It comes up well under irrigated conditions, but does not give a good ratoon. For optimal growth it requires a well drained, fertile soil of pH 6.5-7.5 and adequate moisture. Heavy clays and light sands will produce a successful crop.Acid soils are not tolerated. In China, M. suaveolens is grown on saline soils. Propagation and planting Propagation is by seed, but propagation by cuttings is also possible. Due to a hard testa, seed must be scarified. Seed rate varies from 11-17 kg/ha. Inoculation with effective Rhizobium strains is recommended in fields not previously sown with sweetclover. It has been suggested that it is worthwhile using inoculated seed at each planting. Seeds are small, thus the seedbed should be fine and seed placed no deeper than 1-2 cm in the soil. Husbandry Sweetclover is often sown in mixtures with cereals grown for forage or grain, with grasses, or grown in rotation with cereals. When grown in mixtures with cereals it is left to cover

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the soil in winter and is ploughed in early next spring. The strong taproot opens up the subsoil, providing favourable conditions for growth in succeeding crops. Roots break down and release nutrients rapidly at maturity. Sweetclover is particularly susceptible to injury from herbicides, especially 2,4-D. Diseases and pests Sweetclover is affected by several diseases in the more humid parts of its area of cultivation in the United States and Canada. Phytophthora cactorum causes root rot and crown injury in the spring of the second year. Ascochyta caulicola and Cercospora davisii cause 'black stem', characterized by stunted, blackened stems, poor flowering and reduced seed set. The sweetclover weevil (Sitona cylindricollis) is the main insect pest in North America. Seedlings are most vulnerable, adult plants may be defoliated, but generally survive and outgrow the damage. Harvesting Timing and intensity of grazing or cutting are very important in sweetclover. Intensive grazing or mowing in the first season before the formation of a crown may lead to poor regrowth if there are a limited number of buds on the stem. Grazing or mowing in autumn can prevent adequate development and accumulation of assimilates in the root, leading to poor growth in the second year. Second-year growth is vigorous and heavy grazing is essential when tops are 20-25 cm tall, to keep plants palatable. Good quality hay, equal in palatability and feeding value to lucerne, may be produced from first-year growth. Second-year growth is less satisfactory for hay, as leaves become brittle and shatter in handling. The best quality of silage is obtained from crops cut prior to flowering. Yield Yield of hay varies from 2.2-5.5 t/ha during the first year to 2.2-8.1 t/ha during the second year in the United States. In India, M. alba 'Hubam' has yielded 9.0-10.5 t/ha in 2 cuttings. As a green manure crop, 'Hubam' adds about 80 kg/ha N to the soil. Seed yield averages about 225 kg/ha in the United States, but it has been estimated that about 40% of the seed is lost due to shattering. Genetic resources and breeding A germplasm collection of some 1300 accessions is maintained at the Canada Department of Agriculture, Brandon, Canada. The development of strains with large seed, resistance to seedling diseases, winter hardiness, drought resistance, tolerance to acid and saline soils, and a higher proportion of permeable seed are objectives for improving these crops. Breeding work is being done in Canada, the

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United States and the Russian Federation. Cultivars with low coumarin content have been bred, following the discovery of a low-coumarin gene in M. dentata (Waldst. & Kit.) Pers. and its transfer intoM. alba andM. officinalis. Prospects Sweetclover may regain its former importance in North America and Europe as a green manure and honey crop as more land is left fallow. These 4 Melilotus spp. all occur occasionally naturalized in the tropics, especially in highland areas. Their qualities as soil-improving crops in temperate areas warrant their testing in tropical highland areas. Literature 111 Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 162-170. I2l Gorz, H.J. & Smith, W.K., 1973. Sweetclover. In: Heath, M.E., Metcalfe, D.S. & Barnes, R.F. (Editors): Forages, the science of grassland agriculture. 3th edition. Iowa State University Press, Ames, Iowa, United States, pp. 159-166. l3l Gross, A.T.H. & Stevenson, G.A., 1964. Resistance in Melilotus species to the sweetclover weevil (Sitona cylindricollis). Canadian Journal of Plant Science 44: 487-488. I4l Ha, S., 1993. Genetical studies on interspecific differentiation in the genus Melilotus. Memoirs of the Faculty of Agriculture, Hokkaido University 18: 67-107. 151 Helm, J. & Meyer, D., 1993.Sweetclover production and management. NDSU Extension Service (Publication), North Dakota State University, United States. 161 Sales, F., 1993. Melilotus Miller (Leguminosae): typification and nomenclature. Anales del Jardfn Botânico de Madrid 51: 171-175. 171Smith, W.K. & Gorz, H.J., 1965. Sweetclover improvement. Advances in Agronomy 17: 163-231. 181 Stevenson, G.A., 1969.An agronomic and taxonomie review of the genus Melilotus Mill. Canadian Journal of Plant Science 49: 1-20. 191 Townsend, C.C. & Guest, E., 1974. Leguminales. Melilotus Mill. In: Townsend, C.C. & Guest, E. (Editors): Flora of Iraq. Vol. 3. Ministry of Agriculture and Agrarian Reform, Baghdad, Iraq. pp. 142-149. R.K. Arora &P.N. Mathur

M i k a n i a Willd. Sp. pi. ed. 4,vol. 3(3): 1742 (1803). COMPOSITAE

2ra=36 (M. cordata); 36, 38,72 (M. micrantha) Major species and synonyms -Mikania cordata (Burm.f.) B.L. Robinson, Contrib. Gray herb. 104:65 (1934), synonyms: Eupa-

torium cordatum Burm.f. (1768), Mikania volubilis (Vahl) Willd. (1803). - Mikania micrantha Kunth, Nov. gen. sp. pi. vol. 4: 105 (1820), synonyms: M. orinocenis Kunth (1820), M. subcrenata Hooker & Arnott (1836), M. umbellifera Gardner (1845). Vernacular n a m e s General: mikania (En). - M. cordata: Mile-a-minute (En). Indonesia: brojo lego (Javanese), blukar (Sumatra), hila hitu lama (Ambon). Malaysia: akar lupang, ceroma, selaput tunggul. Philippines: bikas (Bagobo), detidid (Igorot), uoko (Bontok). Thailand: khikaiyan. - M. micrantha: Bitter vine (En). Liane-serpent (Fr). Origin and geographic distribution Most species ofMikania are native to the Americas; the most widely distributed species M. cordata, however, is native to and widespread in South-East Asia including Hainan and Taiwan. M. micrantha is native to Central and South America; it was first observed in Fiji in 1907, in Java in 1951 and is now found in India, Sri Lanka, Malaysia, Indonesia, the Philippines, New Guinea and several Pacific Islands. U s e s Although often considered a nasty weed, Mikania is sometimes tolerated as a spontaneous soil cover in plantation crops e.g. rubber and oil palm, where its growth is limited by shade or where it can be controlled by herbicides. In plantation crops that transmit more light, and to a lesser extent in annual crops, it is considered one of the most noxious weeds. It is especially troublesome in young plantations, where it can quickly overgrow the main crop. Leaves ofM. cordata constitute a highly palatable forage, especially to sheep. They are also used as a poultice for swellings (Taiwan), itches (Malaysia) and wounds (Indonesia). Properties The dry matter digestibility of M. cordata is about 50% and N concentrations range from 2.6-3.4%, Ca concentrations from 1.5-1.9% and P concentrations from 0.6-0.9%. It has high concentrations of Cu, about 18 mg/kg. It has been reported from Malaysia that Mikania cordata contains phenolic or flavonoid substances that inhibit the growth of other plants e.g. rubber, tomato and tropical kudzu (Pueraria phaseoloides (Roxb.) Benth.), and depress nitrification in soils. Description Perennial, trailing or climbing herbs. Stems branched, terete or angular. Leaves opposite, usually petiolate, simple and entire. Inflorescence composed of corymbosely or cymosely clustered, peduncled heads; head 4-flowered, ho-

MlKANIA

mogamous; involucral scales 4, oblong, narrow, subequal; corolla campanulate, 5-fïd, tube narrow; receptacle small, naked; anthers obtuse at base, apex with appendages; style branches 2, slender, long exserting the corolla, pubescent, subobtuse at apex. Fruit an oblongoid, 5-angular achene, usually glabrous; pappus bristles numerous, uni-seriate, equal, scabrid or barbellate. -M. cordata. Scandent herb, often forming a dense tangled mass. Stem subterete or irregularly angular, ribbed, up to 6 m x 2-3 mm, internodes 8-20 cm long, nodes thickened, sometimes with short hairs. Leaf blade triangularovate, 2.5-10 cm x 2.5-7 cm, base cordate or shortly contracted, margin crenate-dentate, sinuate or entire, apex acutely acuminate, subglabrous, dotted with glands beneath; petiole 1-4 cm long. Inflorescence composed of peduncled heads, combined into small dense corymbs, at the top of short lateral branches and in the axils of leaves; peduncle of corymbs very variable in length; peduncle of heads up to 6 mm long; head 6.5-7.5 mm x 1.5-2 mm; involucral

Mikania cordata (Burm.f.) B.L. Robinson - 1, flowering plant part; 2, flower head; 3, achene with flower.

195

bracts elliptical-oblong, 6 mm long; corolla 3.5-4 mm long, yellowish-white; style branches 2.5 mm long, white. Achene 2-3 mm long, glandular, black-brown; pappus of 40-45 bristles, 3-4 mm long, white to reddish. - M. micrantha. Creeping or twining herb. Stem terete to ribbed, pubescent to glabrous; internodes 5-20 cm long. Leaf blade ovate, 2-13 cm x 3-10 cm, base cordate, margin undulate-dentate to subentire, apex acuminate, glabrous; petiole up to 8 cm long. Inflorescence an axillary or terminal panicle of corymbs; peduncle about 6 mm long; flower head 4-6 mm long; involucral bracts ovate-oblong 3-4 mm long, glabrous, apex acute; corolla 2.5-3 mm long, white to greenish. Achene 2 mm long, black, with very small glands between the ribs; pappus of 33-36 bristles, 2-3 mm long, white. Growth and development Mikania spreads by seed or by rooting at nodes touching the soil. Even small pieces of stem, spread by people or animals, may grow into new plants. Flowering occurs throughout the year. Seeds are produced in large numbers and the pappus enables effective wind dispersal over long distances. With its rampant growth it can rapidly smother young tree crops and other plants, hence the common name of M. cordata: 'mile-a-minute'. It can rapidly form a tangled mass to a depth of 0.6-1 m. If undisturbed, it often spreads in massive circular patterns. Other botanical information Mikania comprises about 400 species, many of which are quite variable and difficult to identify. The 2 species treated here have long been considered as one species:M. scandens (L.) Willd.M. scandens, however, only occurs in the Americas. References to M. scandens from Asia usually refer to M. cordata. Distinctive characters ofthe 2 species are: - M. cordata: heads 6.5-7.5 mm long; involucral bracts elliptical-oblong, 6 mm long; corolla yellow-white; achene 2-3 mm long. - M. micrantha: heads 4-6 mm long; involucral bracts ovate-oblong, 3-4 mm long, shortly acute at apex; corolla white; achene up to 2 mm long. Ecology M. cordata is adapted to hot, humid tropical environments with 1500 mm or more annual rainfall and plenty of sunlight, at altitudes ranging from sea level to 1600 m. Hence it is commonly found in young secondary jungle, forest clearings, abandoned ground, secondary regrowth areas, ravines, mountain slopes, roadsides, water courses, fallow land, low-lying areas along streams and rivers and open plantations. Howev-

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er, it can also persist with reduced vigour in plantations. It may even be found under closed canopies of 4-5-year-old rubber and oil palm, but it is then markedly etiolated and weakened. It is rarely found in plantations 5-15 years old. M. micrantha is usually found in damp clearings in lowland forest, but occurs up to 3000 m altitude. In Indonesia, it is only found below 700 m altitude. It grows along streams and roadsides, on disturbed sites as well as in forests. In Latin America it is only rarely a weed, but in parts of Asia it is considered the most aggressive species. Agronomy Mikania can be a devastating weed in crops of tea, coconut, cocoa, rubber, oil palm, coffee, banana and sugar cane, and can smother leguminous cover crops. Spraying with herbicides can reduce its vigour and spread. Mechanical weeding may contribute to the distribution of Mikania by spreading pieces of stem. As a cover crop, Mikania quickly covers the soil, but produces only small amounts oforganic matter or leaf litter compared with leguminous or grass covers. Yields of associated rubber and oil palm are often lower than with a bush or legume cover. This is attributed not only to competition for nutrients and water, but also to allelopathic compounds diffusing from the roots. It has been reported as being susceptible to parasitic growth of dodder, discuta chinensis Lamk in Sri Lanka and C. australis R. Br. in Fiji and Malaysia. M. cordata is palatable to livestock, particularly to sheep. Where present, it is the first species to be eliminated when sheep graze pastures. It should not be the main component of forage for sheep. Instances of abortion, death of newborn lambs and of older sheep have been recorded in rubber plantations where it comprised more than 50% ofthe diet. There is evidence that these problems relate to the high Cu concentrations. In Africa, M. cordata is reported to be less palatable to cattle and intensive grazing may lead to disappearance of grasses in mixed swards. There is very little information about the productivity of Mikania. Dry matter yields of 4 t/ha have been found in Mauritius. Genetic resources and breeding It is unlikely that any germplasm collections or breeding programmes ofMikania exist. Prospects M. cordata and M. micrantha are aggressive herbs that are primarily noxious weeds. They should only be used as a cover crop if a legume cover can not be economically maintained. M. cordata and M. micrantha are highly acceptable, aggressive forages, but further study should be given to their agronomy and to feeding systems

using these species, so that grazing may contribute to the biological control of these serious weeds. Literature 111 Barnes, D.E. & Chandapallai, M.M., 1972. Common weeds ofMalaysia and their control. Longman Malaysia Sendirian Berhad, Kuala Lumpur, Malaysia, p. 93. 121 Broughton, W.J., 1977. Effect of various covers on soil fertility under Hevea brasiliensis Muell. Arg. and on growth of the tree. Agro-Ecosystems 3: 147-170. 131 Chen, C.P. & Chee, Y.K., 1992. Mikania cordata (Burm.f.) B.L. Robinson. In: 't Mannetje, L. & Jones, R.M. (Editors): Forages. Plant Resources of South-East Asia No 4. Pudoc Scientific Publishers, Wageningen, the Netherlands, pp. 166-167. 141 Devendra, C , 1979. Malaysian feedingstuffs. Malaysian Agricultural Research and Development Institute (MARDI), Kuala Lumpur, Malaysia, p. 29. 151 Holm, L.G., Plucknett, D.L., Pancho, J.V. & Herberger, J.P., 1977. The world's worst weeds: distribution and biology. East-West Center, University of Hawaii Press, Honolulu, Hawaii, United States, pp. 320-327. 161 Holmes, W.C., 1982. Revision of the Old World Mikania (Compositae). Botanische Jahrbücher 103: 2 1 1 246. 171Koster, J.T., 1935. The Compositae of the Malay Archipelago. 11. Mikania. Blumea 1: 503510. 181Mangoensoekardjo, S. & Soewadji, R.M., 1977. Pengaruh penutup terhadap tanaman karet. 3. Ditinjau dari segi hasil [The influence of ground covers on rubber. 3. Effect on yield]. Buletin Balai Penelitian Perkebunan Medan (Indonesia) 8(4): 117-124. I9l Perry, L.M., 1980. Medicinal plants of east and southeast Asia: attributed properties and uses. MIT Press, Cambridge, Massachusetts, United States, p. 103. llOl Wong, R., 1964. Evidence for the presence of growth inhibitory substances in Mikania cordata (Burm.f.) B.L. Robinson. Journal of Rubber Research Institute ofMalaya 18: 231-242. LB. Ipor &H. Sutarno M i m o s a d i p l o t r i c h a C. W r i g h t e x Sauvalle Anal. Acad. Cienc. Med. Fis. & Nat. Habana 5: 405(1869). L E G U M I N O S A E - MlMOSOIDEAE

2« =24 Synonyms Mimosa invisa Martius (1837), non Martius ex Colla (1834). Vernacular n a m e s Giant sensitive plant (En). Giant false sensitive plant (Am). Indonesia: sime-

MIMOSA

duri-dura (Malay), jukut borang (Sundanese). Malaysia: duri semalu. Philippines: makahiang lalake (Tagalog). Cambodia: bânla: sâ-'ot. Laos: hnha:z khè:wz ngu:. Thailand: maiyarap-thao. Vietnam: c[aa]y trinh n[uwx] m[os]c. Origin and geographic distribution M. diplotricha is native to tropical and subtropical America from north-eastern Argentina and southeastern Brazil to south-western Mexico and the Greater Antilles; its distribution is now pantropical. It was probably accidentally introduced into South-East Asia in the 19th Century. In the early 20th Century it was taken into cultivation in Java and Sumatra and from there to other countries in South-East Asia. A true-breeding, spineless form was discovered in Java in 1942 and soon taken into cultivation; this form spread to most countries of South and South-East Asia and to a lesser extent to Africa. Uses The typical, spiny form of M. diplotricha used to be cultivated as a green manure, fallow crop and cover crop. However, it is now considered a noxious weed because it aggressively colonizes open spaces, produces large amounts of easily distributed seed and may pose a fire hazard. Because ofits spines, it is especially notorious in hand-harvested sugar cane. The spineless form is still cultivated. It is an excellent soil improver, cover crop and soil binder against erosion in humid areas, but is somewhat less effective in smothering weeds than the spiny form. Until 1940, M. diplotricha had been used as a fallow crop in wrapper tobacco cultivation in Deli, Sumatra, because it significantly reduced the incidence of Granville wilt or slime disease caused by Pseudomonas solanacearum. As it was difficult to eradicate the fallow crop later and it slightly reduced the quality of the tobacco leaves, this use has been discontinued. In the Philippines the Italian honeybee, Apis mellifera, collects large amounts of pollen of M. diplotricha and M. pudica L. during the distinct 'Mimosa pollen season' (October-March). At this time over 80% of the pollen collected originates from Mimosa species. Properties Information on the properties of M. diplotricha is scanty. Mature spiny plants discourage animals from grazing them, although buffaloes are said to eat young shoots. Pigs are reported to be poisoned by ingesting large amounts, probably ofthe spineless form. The weight of 1000 seeds is about 6 g. Description A straggling or scrambling, shortlived perennial woody shrub or semi-woody herb,

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Mimosa diplotricha C. Wright ex Sauvalle - 1, flowering branch; 2, leaflet; 3, flower; 4, fruiting branch; 5,pod; 6, seed. with branches to over 5 m long, rooting at the base and with a strong, elaborate rooting system. Stem 4-5-angular, prostrate or ascending, up to 1-2 m tall, slightly purplish to brown, hirsute, on the angles with strong, recurved, sharp, yellow spines 3-4 mm long. Leaves bipinnate, with 3-10 pairs of evenly distributed, opposite pinnae; petiole 2-7 cm long, thickened at the base; rachis 6-11 cm long, thickened at the base; petiole and rachis furrowed, hirsute, armed with 4 rows of recurved prickles; stipels transformed into prickles at the bases ofthe pinnae; pinnae 1-4.5 cm long, hirsute, with recurved prickles abaxially; leaflets opposite, in 11-30 pairs per pinna, oblong, acute, (2-) 3.5-5(-7) mm x 1-2 mm, sensitive to the touch or movement, with scattered hairs on both surfaces. Inflorescence a glomerule (globose head), mostly (l-)2(-3) together in the axil of a young leaf; peduncle 0.5-2 cm long, densely and subpatently villous with recurved spines; bracts spathulate, with ciliate tips, 0.4-1 mm long; flower bisexual, sub-

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sessile, actinomorphic, 4-merous; calyx campanulate, small, up to 0.4 mm long; corolla narrowly funnel-shaped, 1-2.8 mm long, whitish, finely puberulous or glabrous, with 4 ovate, 1 mm long lobes that are greenish with purplish margin; stamens 8, filaments free, pale purplish-pink, 8-16 mm long, strongly exserted; pistil with puberulous ovary, style purplish-red and as long as the stamens. Pod borne in umbelliform clusters, sessile, flattened oblongoid, slightly curved, 1-3.5 cm x 4-5 mm, acuminate at apex, 3-8-seeded, sharply bristly, at maturity breaking into free-falling, 1seeded articles, sutures persistent. Seed flattened rhomboid or ovoid, 2-5 mm in diameter, glossy yellowish-brown. Growth and development M. diplotricha has a robust growth and scrambles over other plants forming spreading, tangled masses or thickets of undergrowth up to 2 m tall, eventually forming pure stands. The duration of growth is 1.5-2 years, at the end of which time the plant dies. With fast-growing Rhizobium similar to the form infecting Leucaena leucocephala (Lamk) de Wit it forms root nodules and fixes atmospheric nitrogen. In Indonesia, Malaysia and the Philippines it flowers and fruits throughout the year. Other botanical information M. diplotricha has long been known as M. invisa Martius, and the latter has long been thought to be identical with M. invisa Martius ex Colla which, however, is a different species from South America with larger leaves (4-21 pairs of pinnae, 17-50 pairs of leaflets), with spiciform inflorescences and larger fruits (up to 14.5 cm long).M. diplotricha has been subdivided into 3 varieties: - var. diplotricha: spiny; fruits l-2.5(~3.2) cm long, containing 2-8 seeds; distributed all over tropical America and pantropically as a weed; - var. odibilis Barneby: spiny; fruits 4-7 cm long, containing 12-16 seeds; only known from Mexico; - var. inermis (Adelb.) Veldkamp (synonym: M. invisa Martius var. inermis Adelb.): spineless, for the rest like var. diplotricha; the spineless form originated in Indonesia, where it gradually replaced the spiny forms as soil cover in plantations; spineless forms have also been discovered in other tropical areas, but unlike the Javanese form, most ofthem do not breed true. Ecology M. diplotricha is an aggressive colonizer on light and heavy, moist, often poor soils, in sunny to lightly shaded locations, along drains, water courses and roadsides, in ravines, in annual and perennial crops and in secondary forest. In

drier areas it is restricted to depressions and other damp sites. The plant may die during prolonged dry spells. It occurs at various altitudes, from 0-2000 m above sea level. Although it prefers light, permeable soils, it can also be grown on heavy clay soils. Propagation and planting M. diplotricha is propagated by seed. Seed kept in 98°C hot water for 1.5 minutes or in 98% sulphuric acid for 20-30 minutes showed a high percentage of germination. Dry heat has also given a high germination rate. Seed is sown in rows about 5 m apart at a rate of 6-8 kg/ha. Pods of the spiny forms have spiny surfaces and are easily distributed by animals and farm machinery. The seed may germinate immediately or remain dormant in the soil for a long period. Seed collected about 50 days after flowering gives the highest direct germination rate. Husbandry As a cover crop in tree plantations the spineless forms will last for 1.5-2 years (under favourable conditions 4 years) and then gradually die. It is cheaper to establish, covers the soil more quickly and can be better established on poorer soils than most other leguminous cover crops. The spiny forms are most effective in suppressing lmperata cylindrica (L.) Raeuschel but do not kill it and the grass may recover after M. diplotricha is phased out. The spineless form is less effective in smothering weeds. In rubber estates in Indonesia and Malaysia M. diplotricha was prevented from climbing trees and its growth was checked by pulling its branches back and beating them down with bamboo sticks. Rubber trees in Sri Lanka and coconut palms in India grew better with a cover crop of M. diplotricha than with a natural cover, but in coffee plantations in Cameroon its use is not recommended because of the risk of fire in exceptionally dry periods. In replanting experiments in tea conducted in Tocklay (India), a soil cover of M. diplotricha for 2 years followed by subsoiling resulted in much faster establishment and better growth oftea plants than direct planting or planting of tea after subsoiling alone. In tests in Thailand maize yields gradually increased in a rotation with leguminous green manure crops and moderate fertilizer applications, while fertilizer alone could not maintain yields. M. diplotricha and Lablab purpureus (L.) Sweet gave the best results. M. diplotricha is a host of crickets and grasshoppers that feed on coconut palm and oil palm. The main disadvantage of M. diplotricha var. inermis, however, is that it may cross with spiny forms and thus contribute to the spread of

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the latter. In Cameroon a cover crop of var. inermis was kept free of spiny forms by roguing them twice per year during weeding rounds. As a weed, M. diplotricha is effectively controlled by cultivation and hand weeding when plants are still young. It can be controlled by foliar spraying with a wide range of herbicides. The experimental use oflarvae ofthe cerambycid insect Milothris irrorata as biological control against Mimosa pigra L. gave promising results. The larvae tested also attacked M. diplotricha. The larvae attack by boring the stems, while the adults girdle some of the shoots causing them to dry out. Diseases and pests Few diseases and pests have been reported, but M. diplotricha is sensitive toMeloidogyne nematodes. Genetic resources and breeding No substantial germplasm collections or breeding programmes are known to exist. Prospects Although its ease of establishment and effectiveness against Imperata cylindrica are very favourable attributes, the difficulty of controlling its spread and regrowth and the risk of getting spiny forms through crossing with wild plants have limited the use of M. diplotricha var. inermis as a cover crop and green manure. It will probably continue to be used on a minor scale only, because good alternatives, such as Pueraria phaseoloides (Roxb.) Benth., have been selected. Literature 111Barneby, R.C., 1991. Sensitivae censitae. A description of the genus Mimosa Linnaeus (Mimosaceae) in the New World. Memoirs of the New York Botanical Garden 65: 200-203. 121 Bouharmont, P., 1979. L'utilisation des plantes de couverture et du paillage dans la culture du caféier Arabica au Cameroun [The utilization of cover crops and mulching in the cultivation of arabica coffee in Cameroon]. Café, Cacao, Thé 23: 75-102. 131 Holmes, LG., Plucknett, D.L., Pancho, J.V. & Herberger, J.P., 1977. The world's worst weeds, distribution and biology. East-West Center, University Press of Hawaii, Honolulu, United States. pp. 328-331. 141 Ishizawa, S., 1972. Root nodule bacteria of tropical legumes. JARQ (Japanese Agricultural Research Quarterly) 6(4): 199-211. I5l Nielsen, I.C., 1992. Mimosaceae (Leguminosae Mimosoideae). In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana, Series 1,Vol. 11.Foundation Flora Malesiana, Leiden, the Netherlands, pp. 184-185. 161 Payawal, P.C., Tilde, A.C. & Manimtin, A.L., 1986. Year round pollen sources ofItalian honeybee (Apis mellifera L.) in Los Banos area. The Philippine Agriculturist 69(2): 217-225. 171 Sukthumrong, A.,

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Chotechaungmanirat, S., Chancharoensook, J. & Veerasan, V., 1987. The effect of green manurechemical fertilizer combinations on soil fertility and yield ofcorn. Extension Bulletin No 246. Asian and Pacific Council, Food & Fertilizer Technology Center, Taipei, Taiwan. 10 pp. I8l Sukunnarah, N. & Doungsa-ard, C , 1985. Biological studies on the thorny sensitive plant, Mimosa invisa Mart. Journal of Agricultural Research and Extension (Thailand) 2(4): 189-194. I9l Suryatna, E.S. & Mcintosh, J.L., 1982.Weed control in shifting cultivation and permanent agriculture. Biotrop Special Publication No 15: 63-73. llOl Yogaratram, N., Sulaiman, H , Karunaratna, A.D.M. & Peiris, K.S.A.C, 1977. Management of covers under Hevea in Sri Lanka. Journal of the Rubber Research Institute of Sri Lanka (RRISL) 54(1):291-298. C. Doungsa-ard &C.S. Tawan

M u c u n a p r u r i e n s (L.) D C . c v . g r o u p Utilis M. pruriens: Prodr. 2: 405 (1825); cv. group Utilis: Westphal, Pulses in Ethiopia, their taxonomy and agricultural significance: 121(1974). LEGUMINOSAE - PAPILIONOIDEAE

2n =20, 22, 24 Synonyms Mucuna utilis Wall, ex Wight (1840), M. pruriens (L.) DC. var. utilis (Wall, ex Wight) Baker ex Burck (1893), M. pruriens (L.) DC. f. utilis (Wall, ex Wight) Backer (1963). Vernacular n a m e s Velvet bean (En). Cowitch (Am). Pois mascate, pois velus (Fr). Indonesia: kara benguk (Javanese), kowas (Sundanese), kekara juleh (Moluccas). Malaysia: kacang babi, kekaras gatal. Philippines: sabawel. Cambodia: khnhaè. Laos: tam nhè. Thailand: mamui (central). Vietnam: d[aaj]u m[ef]o r[uf]ng. Origin and geographic distribution Velvet bean is probably a native of tropical South or South-East Asia, and has been widely distributed throughout the tropics. It was introduced into Florida in 1876, from where its range was extended into temperate and subtropical areas by breeding. In the south-eastern United States it used to be the most important cover crop grown in combination with maize in an area of about 1000 000 ha around 1920. Later, soya bean and commercial fertilizers rapidly replaced it and it disappeared from agricultural statistics in 1965. As a cover crop, it is now most important in Australia, Hawaii, the Fiji Islands, Indonesia, Malaysia and the Philippines.

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Uses Velvet bean is mainly grown as a cover crop and green manure and is one of the most suitable crops for reclaiming land infested with weeds, especially with Cynodon dactylon (L.) Pers., Cyperus rotundus L. and Imperata cylindrica (L.) Raeuschel. It is recommended for use in rotation with cotton in Brazil to limit Fusarium oxysporum and Meloidogyne incognita infestation. In Central America, it is widely grown either relay planted with maize or as a rainy season fallow crop in rotation with dry season maize. It was formerly an important cover crop in citrus and banana plantations. In Georgia and northern Florida and in Mauritius it is used as a forage and as a component in pastures. Boiled seeds of velvet bean are occasionally eaten as a pulse. In Java the seeds are fermented and flattened into a kind of cake ('tempe benguk'), while immature pods and young leaves are sometimes boiled as vegetables. In the southern United States it is often grown as an ornamental. In traditional medicine the pod hairs mixed with syrup, molasses or honey are taken as an anthelminthic, but the effect seems to be only minor. Ethanol extracts of the pod-hairs and leaves have an analgesic and anti-inflammatory effect in rats. The amino acid L-dopa used in the symptomatic relief of Parkinson's disease is extracted from the seed. Starch from the seed has been tested in Brazil in the preparation of food thickeners and adhesives. Production and international trade Annual world seed production has been estimated to be 900 000 t. There is local trade in seed for consumption and in pod hairs. In Java, seed is currently (1996) sold at about US$ 1.00 per kg. No statistics are available on trade and production of seed for manufacturing L-dopa. Properties Analysis of the aboveground organic matter indicates the following composition per 100 g dry matter: protein 15-24 g, ether extract 2 g, N-free extract 49 g, crude fibre 19 g, ash 15 g. Velvet bean plants decompose fairly rapidly, the rate may amount to 50% loss of dry weight in about 4 weeks. Per 100 g dry matter seed contains: protein 23-33 g, crude fat 6 g, N-free extracts 52-57 g, fibre 7 g, ash 3.5 g, K 1.5 g, P 1g, Ca 0.2 g, vitamin A 50 IU. The in vitro protein digestibility in cattle is about 72%. The nutritive value of the seed, either raw, boiled or roasted, is not very high, similar to e.g. Lima bean (Phaseolus lunatus L.), but better than sword bean (Canavalia ensiformis (L.) DC. When fed to pigs in large quantities, seed causes severe

vomiting and diarrhoea, probably due to the presence of L-dopa. Two important non-protein amino acids are found in the seed and in smaller amounts in the stems and leaves: L-dopa (L-3.4dihydroxyphenylalanine) from which dopamine, an important medicine to relieve the effects of Parkinson's disease, is prepared, and DMP (N-dimethyltryptamine) which has hallucinogenic properties. The L-dopa content varies from 1.63.3% and is sufficiently high for commercial extraction. The seed also contains a number of alkaloids, the most important of which being mucunaine, prurienine and serotine. The stinging hairs of velvet bean, used as an anthelmintic, contain a pruritogenic, proteolytic enzyme and granular matter, tannic acid and resin. The weight of the seed varies greatly between cultivars, and ranges from 550-850 g per 1000 seeds. Description A vigorous, climbing, pubescent annual herb, 2-18 m long. Roots numerous, 7-10 m long, taproot with many laterals. Stem slender, terete, slightly pubescent with white, straight, short and long hairs, glabrescent. Leaves alternate, 3-foliolate; stipules caducous, subulate, about 0.5 cm long, white-hairy outside, glabrous inside; petiole (3-)4-9(-13.5) cm long, slightly grooved above, generally slightly pubescent, pulvinus pubescent; rachis (0.5-)l-2 cm long, grooved above, slightly pubescent; stipels filiform; lateral leaflets conspicuously asymmetrical, obovate, rhombic, ovate or elliptical, (5-)7-15(-19) cm x (3-)5-12(-17) cm, terminal leaflet symmetrical and as a rule smaller, apex acute to acuminatemucronate, base rounded, covered with appressed, grey or silvery hairs turning black when dry. Inflorescence an axillary raceme, up to 32 cm long, 1-many-flowered, silvery pubescent; rachis tubercled without lateral branchlets; bracts early caducous, narrowly triangular-elliptical, 5-10 mm long; pedicel 1.5-10 mm long, with 2 bracteoles 10 mm x 2 mm, near the base ofthe calyx; calyx campanulate, tube 4-7 mm long, 5-lobed, appressed silvery pubescent outside, glabrous inside, upper pair of lobes connate, the other 3 lobes subequal, triangular, 3-9 mm long, acute; corolla blackishpurple, pale lilac or white; petals clawed, auricled; standard hood-shaped, much shorter than other petals, 17-22 mm x 11-15 mm, fleshy especially towards the base, rounded at the top; wings narrowly obovate, 32-35 mm x 8-10 mm, fleshy especially towards the base, rounded at the top, finely and patently pubescent at base; keel about 35 mm x 5 mm, narrow in the middle, entirely split dorsally, ciliolate at the edges, glabrescent towards

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ground in 2-3 months, forming a thick even blanket about 60 cm deep, smothering most weeds. Its climbing habit further contributes to its capacity to suppress the growth of weeds. Distribution of the roots tends to be very shallow and concentrated in the fertile topsoil. Roots form where creeping stems touch the soil. Velvet bean forms root nodules with slow-growing Rhizobium and fixes atmospheric nitrogen. Flowering commences 90-145 days after sowing and pods begin to ripen 2-3 months after flowering. Self-pollination is the rule. The first harvest ofdry seed may be expected after 200-230 days. Rapid growth declines in most cultivars at an age of 5 months when stems begin to dry and defoliate and roots begin to rot. Maximum survival is generally 8-10 months, but some velvet bean cultivars (Mauritius bean) may cover the ground for over 2 years.

Mucuna pruriens (L.) DC. cv. group Utilis - 1, climbing branches with inflorescence and leaves; 2, young pod; 3, mature pod; 4, seeds. the top, ventrally split near the base and apex, apical part hard and ending in a horny tip; stamens 10, diadelphous. Fruit an oblong, (l-)3(-7)seeded pod with oblique top, somewhat compressed laterally, slightly bulging over the seeds, 4-13 cm x 1-2 cm, finely pubescent with white to light brown hairs; valves thick and leathery, with prominent, complete rib and 2-3 partial, less prominent ribs. Seed oblong-ellipsoid, somewhat laterally compressed, about 15 mm x 10 mm x 5 mm, colour variable, light or pinkish-brown often with dark brown mosaic, mottled with grey, purple or black background, almost entirely black, grey, greyish-black or white; hilum oblong, lateral, eccentric, about 4 mm long, surrounded by a prominent, cream-coloured aril, with scale-like extension at the rim. Seedling with hypogeal germination. Growth and development Young plants of velvet bean have a purplish, pubescent epicotyl; the first 2 leaves are opposite, simple, deeply cordate. They grow very fast and can cover the

Other botanical information M. pruriens has often been classified in the genus Stizolobium P. Br., but at present Stizolobium is generally considered a subgenus or section of Mucuna Adans. Wild forms ofM. pruriens have pods covered with irritating bristly hairs which are absent, or nearly so, in cultivated forms. Several cultivated forms of M. pruriens have been described as distinct species:M. aterrima (Piper &Tracy) Merrill, Mauritius bean, grown as a cover crop and green manure in Australia, Brazil, Mauritius and the West Indies; M. capitata (Roxb.) Wight & Arnott, cultivated in India and Indonesia for its seed; M. deeringiana (Bort) Merrill, Florida or Georgia velvet bean, grown for fodder; M. hassjoo (Piper & Tracy) Mansf. (synonym Stizolobium hassjoo (Sieb.) Piper and Tracy), Yokohama velvet bean, an early maturing type from Japan; M. nivea Wight & Arnott (synonyms M. lyonii Merrill and M. cochinchinensis (Lour.) A. Chev.), Lyon bean, cultivated for the immature pods eaten as a vegetable in South-East Asia; M. pachylobia (Piper & Tracy) Rock (synonym: Stizolobium pachylobium Piper &Tracy), cultivated in India as a green fruit vegetable; M. utilis Wall, ex Wight, Bengal bean, cultivated in India and M. velutina Hassk. All these species, mainly distinguished by the nature of their hairs and colour of flowers and seed are now considered cultivars of M. pruriens cv. group Utilis. A clear classification of the different cultivars into cv. groups is badly needed. Several cultivars differing in plant type and time to maturity have been released in the United States. The best known are: '120-Day Florida', a cultivar with medium-sized, mottled seed, usually requiring over 120 days to mature in the United

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States; 'Early Jumbo', a large-seeded cultivar maturing in about 175 days, easy to harvest for seed because the pods grow in clusters that can be picked together; 'Osceola', a white-flowered heavy seed producer with pods almost devoid of stinging hairs; 'Victor', maturing in about 190 days, producing about 1400 kg seed per ha. Ecology Velvet bean tolerates a wide range of annual rainfall from 400-3000 mm, but is not drought resistant because of its shallow root system. Only Mauritius bean shows better drought tolerance. Velvet bean grows best at an average annual temperature of 19-27°C. Plants are sensitive to frost and exposure to a temperature below 5°C for more than 24 hours is fatal even for cultivars from Florida. A night temperature of over 21°C is said to stimulate flowering. Velvet bean requires a high light intensity and yields poorly when intercropped with cassava or maize. It grows best on well-drained sand and clay soils and on ultisols with a pH of 5-6.5, but also grows vigorously on acidic sandy soils. It does not tolerate waterlogging. In soils with a fertile topsoil and an acidic subsoil, the latter being low in P and high in Al, root growth is concentrated in the topsoil. If a fertile topsoil is absent an extensive root system develops even in acidic soils. Propagation and planting Propagation is mostly by seed. Seed requires no scarification, but dry seed requires soaking in water for 24 hours. The germination rate offresh seed is 90-100%, declining with time. Seed stored in a cool dry place remained viable for about 2 years, but seed stored in a sealed jar for 3 months lost its viability. Germination takes 4-7 days. In South-East Asia, sowing is done from January to May, at the onset of the rainy season. Seed is placed 2 cm deep with 2-4 seeds per hole. For cover crops in rubber plantations in Indonesia and Malaysia, a spacing of 2 m x 1 m or 1.5 m x 1.5 m is recommended, requiring about 15kg seed per ha. In sugar-cane plantations in Mauritius, a spacing of 60-100 cm x 60-100 cm is used. When planted as a green manure crop in Indonesia, it is sown at a spacing of 30 cm x 20-30 cm with 2 seeds per hole, while elsewhere it is also broadcast. When intercropped with maize in the United States, it is sown in rows 90-120 cm apart at a seed rate of4-15 kg/ha. Husbandry After sowing, velvet bean requires 1-2 weedings. Hand weeding is most common, but both pre- and post-emergence herbicides are applied effectively. When grown as a cover crop in tree plantations, velvet bean is mostly grown in combination with other cover crops, because of its

short life span. Species commonly used in such combinations are Calopogonium mucunoides Desv. and C. caeruleum (Benth.) Sauv., Centrosema pubescens Benth. and Pueraria phaseoloides (Roxb.) Benth. Velvet bean is currently being tested in a number of cropping systems, mainly in combination with maize. It is either intercropped, relay planted 15-40 days after sowing of the maize, or grown in rotation. When grown as a green manure crop, velvet bean tends to become weedy when the seed is left to mature. In tests in Nigeria, mowing velvet bean before maturation ofthe seed followed by zero tillage planting of maize effectively solved this problem. Diseases and pests Velvet bean is little affected by diseases, although in Zimbabwe, it is very susceptible to a vine rot of unknown cause that can wipe out the crop. It is resistant but not immune to root-knot nematodes and is attacked by several other Meloidogyne spp. Very few insect and small mammals attack velvet bean possibly because of its high L-dopa content. The velvet bean caterpillar (Anticarsia gemmatalis) in Florida is one ofthe few insects reported to cause damage. In Malaysia, green bugs (Brachyplatys spp.) feed on the leaves. Striga gesnerioides (Willd.) Vatke parasitizes the velvet bean. Harvesting The optimum time for harvesting velvet bean for green manure is at flower initiation, attained 55-145 days after sowing, depending on the cultivar. Plants are pulled up by hand or by hoe and buried in the soil. Grown for forage in the United States, it may be harvested 90-120 days after sowing, when the pods are still young. In Malaysia, the first harvest for fodder can take place 2 months after sowing. A cutting interval of 5 weeks and cutting at a height of 30 cm provide a reasonable yield of forage of adequate quality. Harvesting for pod production can start as soon as the pods start changing colour from green to dark brown or black; in Malaysia this is possible at 215-255 days after sowing. Pods are harvested by hand. When intercropped with maize, cutting velvet bean below the level of the maturing maize cobs facilitates harvesting the latter. Yield On good soils in the southern United States, seed yields of 900-1200 kg/ha and even of 1500 kg/ha in Hawaii have been obtained. In India, seed yields range from 250-1150 kg/ha. Green forage yields in the United States are 3-6 t/ha 90-120 days after sowing and 18t/ha at the end of a growing season. When grown as a cover crop in rubber plantation a fresh organic matter yield of

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about 2 t/ha can be obtained in about 6 months. Handling after harvest Green manure should be buried in the soil immediately after harvesting. If left to dry above the ground, the nitrogen content may be reduced by as much as 50%. Dried pods are threshed with a regular grain thresher or by hand. In Java and Africa, threshing is done by beating the pods put in sacks. Only the best seed is used to make 'tempe'. It is washed and boiled for 2-3 hours. After cooling, seeds are dehulled and soaked in ample water for 1-2 days, changing the water 2-3 times a day to ensure that all toxic substances have been removed. The cotyledons are then chopped into smaller pieces and steamed. When cool, the beans are sieved and inoculated evenly with the fungus Rhizopus arrhizus or R. oryzae, flattened and wrapped in banana leaves or a similar material for 24-40 hours at 31°C. The product is a cake covered with mats of mycelium. It is consumed fried, or mixed with vegetables in a soup. Genetic resources Natural populations of wild forms of M. pruriens are no longer common in Indonesia, while other species of Mucuna, such as M. acuminata R. Grah., M. gigantea (Willd.) DC. and M. macrophylla Miq. are also threatened. Hybridization of cultivated genotypes with these species may become important in breeding programmes. Germplasm collections of Mucuna spp. are maintained, for example at the Southern Regional Plant Introduction Station of the United States Department of Agriculture, Griffin, Georgia, which has 32 accessions ofvelvet bean. Breeding A number of cultivars have been released in the United States, but no current breeding programmes are known to exist. Prospects Velvet bean covers the soil quickly, is very productive, resists most diseases and pests, and is adapted to a wide range of environmental conditions. It is one of the few cover crops and green manures that yield valuable byproducts, making it attractive to small-scale farmers. Its resistance to diseases and pests also make it an attractive vegetable and pulse crop. Its future importance as a source of L-dopa depends on the existence of alternative plant sources and methods ofproducing this compound synthetically. Literature 111 Buckles, D., 1995. Velvetbean: a 'new' plant with a history. Economic Botany 49: 13-25. 121Duke, J.A., 1981. Handbook of legumes ofworld economic importance. Plenum Press, New York, United States, pp. 170-173. I3l Guritno, B., Sitompul, S.M. & van der Heide, J., 1992. Reclamation of alang-alang land using cover crops on

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an ultisol in Lampung. Agrivita 15: 87-89. I4l Hairiah, K., 1992. Aluminium tolerance of Mucuna, a tropical leguminous cover crop. Ph.D. thesis, Rijks Universiteit Groningen, the Netherlands. 152 pp. 151Hairiah, K , Utomo, W.H. & van der Heide, J., 1992. Biomass production and performance of leguminous cover crops on an ultisol in Lampung. Agrivita 15: 39-43. I6l Handayanto, E., Nuraini, Y., Purnomosidi, P., Hanegraaf, M., Achterberg, G., Hassink, J. & van Noordwijk, M., 1992. Decomposition rates of legume residues and N-mineralization in an ultisol in Lampung. Agrivita 15: 75-86. 171Iauk, L., Galati, E.M., Kirjavainen, S., Foretieri, A.M. & Trovato, A., 1993. Analgesic and antipyretic effects of Mucuna pruriens. International Journal of Pharmacognosy 31(3): 213-216. I8l Lubis, I., Sastrapradja, S., Lubis, S.H.A. &Sastrapradja, D., 1981. L-dihydroxyphenylalanine (L-dopa) in Mucuna seeds. Annales Bogorienses 7(3): 107-115. I9l Ridzwan, A.H.M. & Hanam, M.R.F., 1980. The effect of cutting height and cutting intervals on the yield and forage characteristics of Mucuna cochinchinensis. Proceedings oflegumes in the tropics, Universiti Pertanian Malaysia, Serdang, Malaysia. pp. 435-440. N. Wulijarni-Soetjipto &R.F. Maligalig

Paraserianthes falcataria (L.) Nielsen Bull. Mus. Natn. Hist. Nat., 4e sér., sect. B, Adansonia5:327(1983). L E G U M I N O S A E - MlMOSOIDEAE

2« = 26 Synonyms Albizia moluccana Miquel (1855),A. falcata sensu Backer (1908),A. falcataria (L.) Fosberg(1965). Vernacular n a m e s Paraserianthes (general), batai (timber trade name) (En). Peacock's plume (Am). Brunei: puah. Indonesia: jeungjing (Sundanese), sengon laut (Javanese), sikat (Banda). Malaysia: batai (Peninsular, Sabah), kayu machis (Sarawak). Papua New Guinea: white albizia. Philippines: Moluccan sau, falcata. Origin and geographic distribution P. falcataria is native to the Moluccas, New Guinea, the Bismarck Archipelago including the Admirality Islands and the Solomon Islands. It is widely planted throughout the humid tropics. Uses P. falcataria is planted extensively for reforestation and afforestation of denuded and eroding land. Because it is very fast- growing, the wood is widely used for fuelwood and charcoal pro-

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auction in spite of its low density and energy value. It is an important shade tree for tea and other crops, its fast growth and good shading properties outweighing its sensitivity to strong winds and its relatively short life. It is being tested in alleycropping systems, although its tolerance of coppicing is limited. P. falcataria is a major source of paper pulp and has been used for the manufacture of viscose rayon. The comparatively soft timber, called batai in trade, is suitable for general utility purposes such as light construction, furniture and cabinet work, lightweight packing materials and pallets. It is a well-known source for match wood. Because the wood is fairly easy to cut, batai is also suitable for wooden shoes, musical instruments, toys and novelties, forms and general turnery. Batai is an important source of lightweight veneer and plywood and is very suitable for the manufacture of particle board, wood-wool board and hardboard, and has recently also been used for blockboard. The bark yields a gum, has tanning properties, and it is also used for packing. The leaves are fed to poultry, goats and sheep. P. falcataria is also planted as an ornamental. Production and international trade In Japan there is a great demand for batai wood for manufacturing lightweight furniture and furniture components (e.g. drawer sides); particularly the butt log portion is used for these purposes. Timber from natural and plantation-grown trees is imported in Japan, but no statistics are available. Properties In Cameroon, the mineral composition ofthe leaves of 1-year-old trees per 100 g was approximately: N 2.5 g, P 0.15 g, K 0.7 g, and Ca 1.17 g; the composition of the wood: N 0.9 g, P 0.1 g, K 0.4 g, and Ca 0.3 g. In an alley cropping experiment in Western Samoa, P. falcataria was pruned 4 times per year, each pruning producing about 1t/ha total dry matter. The mineral composition of the prunings was: N 5.3 g, P 0.6 g, K 0.8 g, Ca 0.6 g, and Mg 0.3 g. The density of the wood of P. falcataria is (230^)300-500 kg/m 3 at 12% moisture content. The energy value of the wood is 19 500-20 600 kJ/kg. Batai is a lightweight, soft to moderately soft wood. The colour of the heartwood ranges from whitish to pale pinkish-brown or light yellowish- to reddish-brown (in older trees); the heartwood of younger trees is not clearly demarcated from the pale coloured sapwood, but it is more distinct in older trees. The grain of the wood is straight or interlocked, texture moderately

coarse but even. Batai wood usually air-dries fairly rapidly without serious degrade, and the kilndrying properties are satisfactory. It is easy to work with machines and hand tools, but is reported to be abrasive to saws. Sharp knives are needed to produce smooth surfaces in planing, otherwise grain may pick up badly. The wood moulds and mortises well but tension wood, if present, will give a woolly surface. Boring is usually easy, but the nailing properties are rated as poor. Glueing is no problem. Batai can be peeled and sliced easily into veneer of good quality. It is very suitable for particle boards, while its pulp is rated among the best of tropical woods, comparable to good-quality eucalypt pulp, and requiring only minimal bleaching. The wood is not durable when used outdoors, with an average service life in contact with the ground of 0.5-2 years in graveyard tests. It is very vulnerable to termites, powder-post beetles and fungi. The wood can be treated easily with preservatives, e.g. a mixture of creosote and diesel fuel. Stake tests showed an average life of treated wood in contact with the ground of 15years under tropical conditions. Sawdust from dry wood may cause allergic reactions and may irritate nose and throat. Batai wood contains 49% cellulose, 27% lignin, 15.5% pentosan, 0.6% ash and 0.2% silica. Preliminary test results indicate that the leaves of P. falcataria are a good fodder: daily liveweight gains of57 g were found in sheep, about 50% higher than from leaves of Calliandra calothyrsus Meisn. and Gliricidia sepium (Jacq.) Kunth ex Walp. The weight of 1000 seeds is 16-26 g. Description Amedium-sized to fairly large, unarmed tree up to 40 m tall, bole straight and cylindrical in dense stands, branchless for up to 20 m and up to 100 cm or sometimes more in diameter; bark surface white, grey or greenish, smooth or slightly warty, sometimes shallowly fissured and with longitudinal rows of lenticels, inner bark white, yellowish, pink or pale red-brown, fibrous; young parts often densely tomentose. Leaves alternate, bipinnate, up to 40 cm long, with (4-)8-15 pairs of pinnae, each pinna with (8-)15-25 leaflets, rachis and pinnae with extrafloral nectaries; stipules linear or filiform, caducous, 3-5 mm x 0.5-1 mm; petiole 2-8 cm long, with a raised gland in the distal half; leaflets oblong-falcate, 6-15 mm x (2-)3-6 mm, sessile, densely appressed puberulous. Inflorescence a paniculate raceme, up to 30 cm long; flowers bisexual, 5-merous, sub-

PARASERIANTHES

Paraserianthes falcataria (L.) Nielsen - 1, tree habit; 2, flowering twig with part of leaf; 3, flower; 4, pod. tended by bracts; calyx valvate, tubular to cup- or bell-shaped, 1.5-3 mm long; corolla valvate, funnel- or bell-shaped, 4-6.5 mm long, creamy to yellowish, sericeous all over; stamens numerous, 10-15 mm long, white, filaments fused into a 3.5 mm long tube at base, anthers quadrangular, minute; ovary solitary, glabrous. Fruit a chartaceous, flat, straight pod, 7.5-10.5 cm x 1.3-1.7 cm, narrowly winged along the ventral suture, dehiscent along both sutures, puberulous, usually glabrescent, many-seeded. Seed oblongoid, flat, 6-7.5 mm x 3-4 mm, olive-green, with oblong aréole about 5 mm long. Growth and development P. falcataria grows so fast that it is sometimes called the 'miracle tree'. It is even mentioned in the Guinness Book of Records as the world's fastest growing tree. On good sites, trees may attain a height of 7 m in a little more than one year. Trees reach a mean height of 25.5 m and a bole diameter of 17 cm after 6 years, 32.5 m and 40.5 cm after 9 years, 38 m and 54 cm after 12 years, and 39 m and 63.5 cm

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after 15years, respectively. Growth ofyoung trees in a P-deficient soil is promoted by inoculation with the mycorrhizal fungi Gigaspora margarita and Glomus fasciculatum. Inoculation with Bradyrhizobium has proved to be effective, and especially beneficial in combination with mycorrhizal infection. Trees may already flower at the age of 3 years. Two flowering periods per year have been observed in Peninsular Malaysia and Sabah. Ripe pods appear approximately 2 months after flowering. The pods dehisce when ripe, often still attached to the tree, scattering the seeds on the ground. Other botanical information Three subspecies are recognized in P. falcataria. Subsp. falcataria occurs in the Moluccas and New Guinea, subsp. solomonensis Nielsen in the Solomon Islands, and subsp.fulva (Lane-Poole) Nielsen (synonyms: Albizia fulva Lane-Poole and A. eymae Fosberg) in the central mountains of New Guinea; the latter subspecies has densely puberulous to tomentose pods and a woolly leaf rachis. Ecology As a pioneer species, P. falcataria occurs in primary but more characteristically in secondary lowland rain forest, and also in light montane forest, grassy plains and along roadsides near the sea. It is adapted to per-humid and monsoonal climates with a dry season of up to 2(-4) months and an annual rainfall ranging from 2000-4000 mm, averaging 2800 mm. In its natural habitat it occurs from 0-2300 m altitude. The optimum temperature range is 22-29°C, with mean minimum temperatures of the coldest month of 22-24°C and mean maximum temperatures of the hottest month of 30-34°C. It is found on well-drained sandy and lateritic soils. In natural stands in Irian Jaya P. falcataria is associated with e.g. Agathis labillardieri Warb., Celtis spp., Diospyros spp., Pterocarpus indicus Willd., Terminalia spp., and Toona sureni (Blume) Merrill. When planted, P. falcataria can grow on comparatively poor sites and survive without application of fertilizers. However, it does not thrive in poorly drained, flooded or waterlogged soils. It is sensitive to fire and easily damaged by strong wind. Propagation and planting P. falcataria is strongly light-demanding and regenerates naturally only when the soil is exposed to sunlight. In the forest, Wildlings sprout in abundance when the canopy is open and when the soil is cleared from undergrowth. Wildlings can be successfully collected and potted for planting, but they are delicate and have to be handled carefully.

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Seeds are difficult to collect from the ground since they are small. They are usually collected by cutting down branches bearing ripe brown pods. The seeds can be easily collected from felled trees if the fruits happen to be in the right condition. Untreated seeds germinate irregularly; germination may start after 5-10 days but sometimes it is delayed for up to 4 weeks from sowing. To hasten germination and to make it more simultaneous, seed can be soaked in boiling water for 1-3 minutes, or by immersion in concentrated sulphuric acid for 10 minutes and then washing and soaking in water for 18hours. The germination rate can be as high as 80%to almost 100%. For storage, seeds are air dried for 24 hours and then packed in polythene bags. Stored at 4-8°C, the germination rate after 18 months may still be 70-90%. Seed is usually sown by broadcasting, pressed gently into the soil, and then covered with a layer of fine sand up to 1.5 cm thick. The soil in the seed-bed must be loose and well-drained; application of a surface layer of mulch is advisable and excessive shading should be avoided. The seedlings can be transplanted when they have reached a height of 20-25 cm with a woody stem and a good fibrous root system; this stage can be reached in 2-2.5 months. Container plants are often transplanted into the field when 4-5 months old. The stem is cut back to about 10 cm above the root collar, and the taproot to a length of 20-25 cm. The seedlings are usually planted into the field at a spacing of 2-4 m x 2-4 m. The average annual production of seedlings in the Philippines was 2.1 million in the period 1979-1982. Seed tissue has been successfully used for propagation by tissue culture in the Philippines. Husbandry As initial growth ofP. falcataria in plantations is remarkably fast, weeding generally can be limited to 1 complete weeding and 3 spot weedings during the first year. The application of fertilizers may improve the yield; application of 12.5 kg/ha ofP has been found satisfactory. In agroforestry systems a cutting cycle of 10-15 years is normally used, in combination with annual crops in the first year and grazing by livestock in subsequent years. Pure stands give a good protective cover to prevent erosion on slopes, and they are recommended for this purpose in Indonesia and the Philippines in catchment areas sheltered from typhoons. P. falcataria coppices fairly well, which is advantageous for pulpwood production, but frequent coppicing as in alley-cropping systems quickly exhausts the trees and results in

a high mortality rate and poor regrowth. For timber production, the original stand can be thinned to a density of 250 trees/ha when 4-5 years old, and to 150 trees/ha after 10years. Trees grown for timber must be pruned, as they have a tendency to fork. The cutting cycle is usually 12-15 years. Trees grown for pulp production have a cutting cycle of about 8 years. Diseases and pests Nursery seedlings are susceptible to damping-off caused by fungi ofthe genera Fusarium, Phytophthora, Pythium, Rhizoctonia and Sclerotium. Sterilizing the soil before sowing and applying fungicides to soil and seeds may control the disease. The fungus Corticium salmonicolor causes pink canker or salmon canker. At first, light brown lesions appear on the bark of young trees; they gradually enlarge and develop cracks, the colour turns to pale salmon or pinkish and then mycelium mats appear around the lesions. The disease may seriously damage plantations. Plantations can also suffer from other fungal diseases like red root caused by Ganoderma pseudoferrum. An anthracnose seedling disease caused by a Colletotrichum species has been observed in Sumatra. In 1988 and 1989 gall rust disease caused by Uromycladium tepperianum provoked severe damage in Bukidnon Province (Mindanao, the Philippines). The government banned the transport of logs in and out of Bukidnon Province, and planting was suspended. Plantation pests in Indonesia, Malaysia and the Philippines include stem-borers such as the longicorn beetle Xystrocera festiva and the red borer Zeuzera coffeae (a cossid moth). Leaf-eating caterpillars (e.g. Eurema Manda, E. hecabe and Semiothesa emersaria) may attack seedlings and trees. Aphids have occasionally been a problem on seedlings. Insecticides are commonly used to control these pests. Harvesting Plantations are clear-cut when the cutting age is reached. Usually harvesting is problem-free as the trees are harvested when still comparatively young and consequently have small and lightweight logs which can be yarded and loaded easily. Rapid extraction, conversion and seasoning ofbatai wood is necessary to prevent insect attack and infestation by fungi. The wood is particularly prone to sap-staining attack. Yield P. falcataria is a fast grower and the yield is often high. In 8-12-year rotations, mean annual volume increments of (10-)25-30(-40) m 3 /ha are attained. On fertile soils in Indonesia, mean annual increments of 50-55 m 3 /ha have even been reached in plantations of 9-12 years old (120

PELTOPHORUM

trees/ha when 9 years old and 76 trees/ha when 12 years old). Genetic resources and breeding P. falcataria is planted on a large scale throughout the tropics and the genetic resources are quite comprehensive. Prospects Breeding programmes should be conducted to obtain superior trees in respect to bole shape (preferably long and straight without a tendency to fork) and resistance to diseases and pests. Superior trees can be mass-produced by tissue culture. Literature 111Chauhan, L. & Dayal, R., 1985. Wood anatomy of Indian Albizias. IAWA (International Association of Wood Anatomists) Bulletin 6(3): 213-218. I2l Dayan, M.P., 1989. Moluccan sau - Albizia falcataria (L.) Back. RISE (Research Information Series on Ecosystems) Vol. 1(10): 84-97. 131Eusebio, M.A., Sinohin, V.O. & Dayan, M.P., 1990. Gall rust disease of Albizia falcataria (L.) Back. RISE (Research Information Series on Ecosystems) Special Issue. 14 pp. I4l Griffioen, K., 1954. Albizzia falcata, een goede industrie-houtsoort [Albizzia falcata, a good industrial timber]. Tectona 43: 97-110. I5l Martawijaya, A., Kartasujana, I., Mandang, Y.I., Prawira, S.A. &Kadir, K., 1989. Atlas kayu Indonesia [Indonesian wood atlas]. Vol. 2. Forest Products Research and Development Centre, Bogor, Indonesia, pp. 59-64. 161 Natawiria, D., 1973. Pests and diseases of Albizia falcataria (A. falcata). Rimba Indonesia 17: 58-69. 171National Academy of Sciences, 1979. Tropical legumes: resources for the future. Washington, D.C., United States, pp. 173-177. 181Nielsen, I., Guinet, P. &Baretta-Kuipers, T., 1983. Studies in Malesian, Australian and Pacific Ingeae (Leguminosae-Mimosoideae): the genera Archidendropsis, Wallaceodendron, Paraserianthes, Pararchidendron and Serianthes, part 2. Bulletin du Muséum National d'Histoire Naturelle, 4e sér., sect. B, Adansonia 5: 335-360. I9l Peh, T.B. & Khoo, K.C., 1984. Timber properties of Acacia mangium, Gmelina arborea, Paraserianthes falcataria and their utilization aspects. Malaysian Forester 47: 285-303. 1101 Rojo, J.P., Alonzo, D.S. & Ilic, J., 1993. Paraserianthes Nielsen. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors): Plant Resources of South-East Asia No 5(1): Timber trees: major commercial timbers. Pudoc Scientific Publishers, Wageningen, the Netherlands, pp. 319-325. J.P. Rojo

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P e l t o p h o r u m d a s y r h a c h i s (Miquel) Kurz Journ. As. Soc. Beng. 45(2): 128 (1876), 293 (1877). LEGUMINOSAE - CAESALPINIOIDEAE

In = unknown Synonyms Caesalpinia dasyrhachis Miquel (1861), Peltophorum grande Prain (1897), P. tonkinense (Pierre) Gagnep. (1913). Vernacular n a m e s Peltophorum (En). Indonesia: soga (Palembang), petaian (Lampung). Malaysia: batai, jemerelang. Cambodia: trâse:k. Laos: s'a:z kha:m, sa: fang, sa: ph'ang. Thailand: nonsi (central), arang (north-eastern). Vietnam: lim x[ej]t, lim v[af]ng. Origin and geographic distribution P. dasyrhachis is found in Thailand, Indo-China, Peninsular Malaysia, Sumatra and Borneo. It is also cultivated in many other tropical regions, e.g. in Java. Uses In the first half of the 20th Century, P. dasyrhachis was used as a shade tree mainly in coffee in Java. In central Thailand it is maintained after bush fallow as a shade tree for fruit trees and for its role in soil improvement. Its use in the reclamation of Imperata cylindrica (L.) Raeuschel grasslands is being tested; in Indonesia and Malaysia, young trees planted in tall Imperata grassland and left untended after planting remained alive, but grew slowly. The red-yellow wood is locally used for planks in house-building, but is of little market value. It is suitable as firewood. Medicinally, the bark is used in an infusion for coughs. Properties Due to a fairly high content of polyphenolic substances, leaf litter decomposition is slow, allowing a humus layer to build up in the soil. The yellowish-red heartwood is heavy, but brittle and is attacked by termites and boring insects. The weight of 1000 seeds is about 37 g. Botany A usually deciduous tree, up to 30 m tall, with a straight trunk and rather diffuse crown; root system with well-developed taproot and few superficial lateral roots; trunk up to 70 cm in diameter; bark up to 10 mm thick, reddishbrown inside; young branches reddish-tomentose, glabrescent. Leaves bipinnate, with 5-9 pairs of pinnae and 6-16 pairs of leaflets per pinna; stipules large, bipartite, branches pinnatifid or bipinnatifid; petiole up to 7 cm long, rachis up to 40 cm long, both reddish-pubescent; leaflets oblong-elliptical, 10-25 mm x 4-10 mm, sessile, base acute, obtuse or rounded, apex rounded-emarginate,

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stem diameter of 5 cm in 2 years. Upon pruning, trees resprout abundantly and form a dense hedge. In Lampung (Indonesia), it does not shed its leaves, flowering takes place during the dry season (September-October) and fruits ripen 1 year later. In Indo-China, flowering is from February to April, while new leaves are formed and fruits ripen from May to November. Seed germinates in abundance after a bush fire. P. dasyrhachis (often erroneously spelled 'dasyrrhachis') is related toP.pterocarpum (DC.) Backer ex K. Heyne, an important source of 'soga' dye. P. dasyrhachis can be distinguished by its crown that is uneven and not umbrella-shaped, its branched stipules, and its thick, reddish tomentum. The two species have occasionally been confounded in the literature. In northern Vietnam, a form of P. dasyrhachis occurs with unbranched stipules and early falling bracts, named var. tonkinense (Pierre) K. &S.S. Larsen.

Peltophorum dasyrhachis (Miguel) Kurz - 1, flowering branch; 2, stipule; 3, flower (2 sepals and petals removed); 4, petal; 5, pod; 6, opened fruit part with seeds. finely pubescent, glabrescent, rather glaucous below, shiny above. Inflorescence an axillary, unbranched raceme, 15-30 cm long; bracts linear, 10-12 mm long, persisting until flowers open; pedicel 1.7-4 cm long; calyx deeply 5-lobed, lobes ovate, 10-15 mm x 5-6 mm, densely velvety outside, glabrous inside; petals 5, obovate, 15-25 mm x 10-12 mm, spreading, yellow, hairy towards the base inside; stamens 10,free, filaments 10-15 mm long, woolly at base, anthers dorsifixed; ovary sessile, 5 mm long, hairy, 4-8-ovuled, style filiform, 12 mm long. Pod elliptical, sharp-pointed, 10-15 cm x 2-4 cm, flat, with a wing-like extension 4-5 mm broad on each suture, dull-brown when ripe, later blackish, 4-8-seeded, indéhiscent, often hanging in bunches below the leaves. Seed flattened oblongoid, 10-12 mm x 5 mm, transversely positioned. Seedling with epigeal germination; hypocotyl 4-6 cm long; cotyledons stalked, 3nerved, glabrous. In Malaysia, trees may grow up to 7 m tall with a

Ecology P. dasyrhachis is found in secondary, deciduous or evergreen forest below 800 m altitude with an annual rainfall of 1500-2500 mm. It is mainly found on ultisols. Due to its relatively deep rooting system, it is drought tolerant. Its hairiness and fairly thick bark have been associated with its tolerance of fire. Agronomy P. dasyrhachis is propagated by seed or cuttings. It has been tested as a tree in alley-cropping systems. When unpruned, it provides a rather dense shade to control weeds during fallow periods, and can be managed in hedges without too much shading of inter-row crops. Because its growth rate is slower than that of Leucaena leucocephala (Lamk) de Wit and Gliricidia sepium (Jacq.) Kunth ex Walp., it requires less frequent pruning. When hedges were pruned 2-4 times per year, an annual yield of prunings of 8 t/ha was found in Lampung (Indonesia), containing 200 kg nitrogen. The slow rate of decomposition of the leaves reduces erosion and contributes to the suppression of weeds. Seeds of Imperata cylindrica hardly germinate in soil covered by the leaves. Pew insects have been recorded as damaging the leaves, whereas large stem-boring insects attack older trees. Genetic resources and breeding No germplasm collections or breeding programmes are known to exist for P. dasyrhachis. Prospects Preliminary research has indicated the potential of P. dasyrhachis as an initial treecover in Imperata grasslands and as a first step in the reclamation of degraded land. This needs confirmation by further experimentation. Its possible

PONGAMIA

suitability as a tree for alley cropping also requires further investigation. Literature 111 Ding Hou, 1996. Caesalpiniaceae. Peltophorum. In: Flora Malesiana. Series 1, Vol. 12. Foundation Flora Malesiana, Rijksherbarium, Leiden University, Leiden, the Netherlands, pp. 650-654. |2|Hairiah, K., van Noordwijk, M., Santoso, B. & Syekhfani, M.S., 1992. Biomass production and root distribution of eight trees and their potential for hedgerow intercropping on an ultisol in Lampung. Agrivita 15: 54-68. 131 Handayanto, E., Cadisch, G. & Giller, K.E., 1994. Nitrogen release from prunings of legume hedgerow trees in relation to quality of the prunings and incubation method. Plant and Soil 160: 237-248. I4l Handayanto, E., Nuraini, Y., Purnomosidi, P., Hanegraaf, M., Agterberg, G., Hassink, J. & van Noordwijk, M., 1992. Decomposition rates of legume residues and N-mineralization in an ultisol in Lampung. Agrivita 15: 75-86. 151 Larsen, K., Larsen, S.S., 1980. Leguminosae (Fabaceae), Caesalpinioideae. Peltophorum. In: Vidal, J.E. & Vidal, Y. (Editors): Flore du Cambodge du Laos et du Vietnam. Vol. 18. Muséum National d'Histoire Naturelle, Laboratoire de Phanérogamie, Paris, France, pp. 59-63. 161Sitompul, S.M., Syekhfani, M.S., van der Heide, J. & van Noordwijk, M., 1992. Yield of maize and soybean in a hedgerow intercropping system on an ultisol in Lampung. Agrivita 15: 69-75. 171van Noordwijk, M., Hairiah, K., Sitompul, S.M. & Syekhfani, M., 1992. Rotational hedgerow in intercropping + Peltophorum pterocarpum = new hope for weed-infested soils. Agroforestry Today 4(4): 4-6. I8l Whitmore, T.C. (Editor), 1972. Tree flora of Malaya. A manual for foresters. 2nd edition, Vol. 1. Malayan Forest Records No 26. Longman Malaysia Sendirian Berhad, Kuala Lumpur, Malaysia, pp. 267-268. M.van Noordwijk & Rudjiman

P o n g a m i a p i n n a t a (L.) P i e r r e Fl. For. Cochinch.: t. 385 (1899). LEGUMINOSAE - PAPILIONOIDEAE

In =20, 22 Synonyms Pongamia glabra Ventenat (1803), Millettia novo-guineensis Kanehira & Hatusima (1942),Derris indica (Lamk) J.J. Bennett (1971). Vernacular n a m e s Pongam, Indian beech (En). Pongame oil tree (Am). Arbre de pongolote (Fr). Indonesia: bangkong (Javanese), ki pahang laut (Sundanese), kranji (Madurese). Malaysia: mempari, kacang kayu laut (Peninsular), biansu

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(Sarawak). Philippines: bani (general), balikbalik, balok (Tagalog). Singapore: seashore mempari. Laos: (do:k) ko:m ko:y. Thailand: khayi (Chumphon), yi-nam (peninsular). Vietnam: d[aaly m[aas|u, d[aajy kirn, kh[oor] s|aa]m hoa. Origin and geographic distribution P. pinnata probably originated from India and occurs naturally or naturalized from Pakistan, India and Sri Lanka throughout South-East Asia to northeastern Australia, Fiji and Japan. It has been introduced in Egypt and the United States (Florida, Hawaii). Uses P. pinnata provides two sources of energy: the wood is burnt as a cooking fuel, while the seed-oil is used for illumination. The wood also provides timber for cabinet work and cartwheels and paper pulp. The oil is applied as a lubricant, as a leather dressing in the traditional Indian tanning industry, and in manufacturing soap, varnish and paint. P. pinnata is used in reforestation of marginal land, its extensive root system making it valuable for checking erosion. In Sri Lanka it is grown as a wind-break. The leaves, flowers and seed-cake are used as green manure, the leaves and seed-cake also as fodder. The flowers are a good source of pollen and nectar, yielding a dark honey. The bark can be made into rope. Medicinally, extracts from the leaves, bark and seed are applied as anti-septic against skin diseases and rheumatism. Pounded and roasted seeds used to be utilised as a fish poison. In rural areas, dried leaves are stored with grain to repel insects. P. pinnata is used as a host of the lac insect and of the hemi-parasitic sandalwood Santalum album L. It is occasionally planted as an ornamental because of its attractive flowers. However, the large amounts of flowers, leaves and pods that it regularly sheds make it not very suitable for this purpose. Properties The energy value of the wood is 19 000-20 000 kJ/kg, its specific gravity about 650 kg/m 3 . The yellowish-white wood is coarse, strong, hard and beautifully grained, but not durable. It has a tendency to warp and split in seasoning. Wood fibre is 1000-1200 |im long, 20 pm in diameter and its wall about 4 um thick. Air-dried seed contains per 100 g: moisture 19 g, protein 18 g, oil 28 g and the flavonoids karanjin 1.25 g and pongamol 0.85 g. The seed-oil has a disagreeable odour, is difficult to refine and is inedible. It contains about 70% oleic acid and 11%linoleic acid. The oil and soap made from it have a characteristic reddish-brown colour due to the compound isolonchocarpin.

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The seed-oil is being tested as an anti-feedant and insecticide against several insects, e.g. Oryzaephilus surinamensis and Tribolium, castaneum (both storage pests of rice) and Nephotettix virescens (a vector of the virus causing tungro disease in rice). The oil and its components are being tested as synergists to increase the potency of other insecticides. Botany Evergreen or briefly deciduous, glabrous shrub or tree with spreading branches, 1525 m tall, trunk up to 80 cm in diameter. Bark smooth or faintly vertically fissured, grey. Branchlets with pale stipule scars. Leaves imparipinnate, pinkish-red when young, glossy dark green above and dull green with prominent veins beneath when mature; leaflets 5-9, ovate, elliptical or oblong, 5-25 cm x 2.5-15 cm, obtuse-acuminate at apex, rounded to cuneate at base. Inflorescence raceme-like, axillary, 6-27 cm long, bearing pairs of strongly fragrant flowers; calyx campanulate, 4-5 mm long, truncate, finely pubescent; corolla white to pink, purple inside, brownish veined outside; standard rounded obovate, 1-2 cm

Pongamia pinnata (L.) Pierre - 1, flowering branch; 2, flower; 3, pods.

long, with basal auricles, often with green central blotch, thinly silky hairy; wings oblong, oblique, slightly adherent to obtuse keel; stamens 10, monadelphous, vexillary one free at base, joined to the tube in the middle. Pod short-stalked, oblique-oblongoid to ellipsoid, flat, 5-8 cm x 2-3.5 cm x 1-1.5 cm, smooth, thick-leathery to subwoody, beaked, indéhiscent, 1-2-seeded. Seed compressed ovoid, 1.5-2.5cm x 1.2-2 cm x 0.8 cm, with a brittle coat. Growth of young trees is fairly slow; a growth of 1.3 m in height and 0.4 cm in diameter in 13 months was found in India. In Florida, it sheds its leaves in April and develops new leaves and flowers from May onwards. In India, seed ripens from February to May. Pods do not open naturally and must decay before seed can germinate. P. pinnata nodulates and fixes atmospheric nitrogen with Rhizobium ofthe cowpea group. The taxonomy of the genus Pongamia Ventenat is confused. It is closely related to and is sometimes included in the genera Millettia Wight &Arnott or Derris Lour. Ecology In its natural range, P. pinnata tolerates a wide temperature range. Mature trees withstand light frost and tolerate temperatures of over 50°C. Its altitudinal range is from 0-1200 m. It is fairly tolerant of shade, at least when young. Annual rainfall required is 500-2500 mm, with a dry season of 2-6 months. It occurs naturally in lowland forest on limestone and rocky coral outcrops on the coast, along the edges of mangrove forest and along tidal streams and rivers. Best growth is found on deep sandy loams, but it will also grow on sandy soils and heavy swelling clay soils. It is very tolerant of saline conditions and tolerant of alkalinity. Agronomy P. pinnata can easily be propagated by seed and cuttings. Even branches stuck in moist soil develop roots readily. Seed remains viable for a long time. No seed treatment is required. Germination takes 10 days to 1month. In the nursery, it can be planted at a close spacing and tolerates shade well. In India, a spacing of 7.5 cm x 15 cm is recommended. Seedlings reach a height of 60 cm about 1.5 years after sowing and are easy to transplant. Direct sowing is common and mostly successful. Trees coppice well and can also be pollarded. Spontaneous seedlings and root suckers are produced in large numbers and may create serious weed problems. P. pinnata is host to a large number offungi and insects, but serious damage has not been reported. Pod production starts 5-7 years after sowing. Individual trees yield 9-90 kg of pods annually. Ripe pods are col-

PROSOPIS

lected in India from April-June and are subsequently dried in the sun. Seeds are easily extracted by light hammering or by splitting the pod with a knife along the sutures and winnowing out of the husks. Mature trees yield 8-24 kg seed annually. Genetic resources and breeding No germplasm collections or breeding programmes are known to exist. Prospects P. pinnata is likely to remain important as a reforestation and fuelwood tree because of its adaptability to poor and saline soils, its many useful products and ease of planting. More research attention to develop its potential as insecticide and as medicine seems warranted. Literature 111 Axtell, B.L. & Fairman, R.M., 1992. Minor oil crops. FAO Agricultural Services Bulletin 94. Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 153-155. I2l Morton, J.F., 1991. The pongam tree, unfit for Florida landscaping, has multiple practical uses in under-developed lands. Proceedings of the Florida State Horticultural Society 103: 338-343. 131 National Academy of Sciences, 1980. Firewood crops. Shrub and tree species for energy production. Vol. 1.National Academy Press, Washington, D.C., United States, pp. 42-43. I4l Philip, E. & Syed, S.B., 1994. Leaffall patterns of Pongamia pinnata in two different sites: A preliminary observation. Transactions of the Malaysian Society of Plant Physiology 5: 189-191. 151 Singh, M.P., Jain, B.P., Srivastava, J.L. & Trivedi, R.N. (Editors), 1991.Nitrogen fixing and multipurpose tree species for afforestation. Today and Tomorrow's Printing & Publishers, New Delhi, India, pp. 192-195. 161 Verdcourt, B., 1979.Amanual of New Guinea legumes. Botany Bulletin No 11. Office of Forests, Division of Botany. Lae, Papua New Guinea, pp. 311-314. L.P.A. Oyen

Prosopisjuliflora (Swartz) DC. Prodr. 2:447(1825). L E G U M I N O S A E - MlMOSOIDEAE

2^ = 26,28,52,56 Synonyms Mimosa juliflora Swartz (1788), Prosopis vidaliana Naves (1877). Vernacular n a m e s Mesquite (En). Bayahonde (Fr). Algarrobo, mesquite (Sp). Origin and geographic distribution P. juliflora probably originates from Peru and occurs naturally in dry areas of northern South America

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and Central America, Mexico and the southern United States. It has been introduced into many dry tropical areas, including north-eastern Brazil, Africa, Australia, South-East Asia and the Indian subcontinent. In Malesia, it is cultivated in Java, Papua New Guinea and the Philippines. In Brazil, cultivation is becoming very important. Uses P.juliflora is widely planted for land reclamation, being an aggressive colonizer, tolerant of very poor, degraded, saline and alkaline soils. It controls soil erosion, stabilizes sand dunes and is planted in wind-breaks and shelter-belts. However, because of its aggressive nature, it is considered a noxious weed in more humid areas, e.g. the southern United States. The generally crooked stems and branches make a good firewood and provide excellent charcoal. The wood is durable and can be used for quality furniture, doors and flooring, but the small trees rarely produce marketable logs. A reddish-amber gum, similar in properties to gum arabic produced byAcacia Senegal Willd., often exudes from the stem and older branches. The protein and sugar-rich pods are valuable livestock fodder, and serve as security food for people during famine. In Argentina, Chile and Peru the pods are an important human food item used in making bread, syrup, sweets and alcoholic drinks such as cocktails. The pods must be processed, to improve the flavour. Sugars and sweeteners can be produced from the pods. Roasted seeds are used as a coffee substitute. Flour prepared from the pods can replace wheat bran in animal feed. For dairy cows, the flour may make up 40-60% of concentrate rations, while in South Africa, it is fed unmixed to sheep. The short-fibred parts are also suitable for pigs and poultry. The leaves of most selections are unpalatable to livestock. P. juliflora is also a valuable honey plant. Medicinally, the pods are used (as tea or syrup) against digestive disturbances and skin lesions. Production and international trade The fruits of P. juliflora are of great economic importance locally in Argentina, Brazil, Chile and Peru, but no statistics are available. Potential agro-industrial uses are being investigated and are promising. Charcoal made from P. juliflora wood is used extensively as a barbecue fuel in the United States, where about 30% of the charcoal sold for this purpose originates from P. juliflora from the Sonora desert in northern Mexico. Properties The wood of P. juliflora is hard and durable and burns evenly. The basic density of sawlogs is about 935 kg/m3, of fuelwood about 750 kg/m 3 . The energy value of fuelwood is

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17000-19 000 kJ/kg. Pods of P. juliflora contain per 100 g: crude protein 14 g, ether extract 3 g, nitrogen-free extract 50 g, crude fibre 28 g, ash 5 g; the flour has more protein and less fibre and carbohydrates. Seed contains per 100 g dry matter: crude protein 41 g, ether extract 5 g, nitrogen-free extract 43 g, sugars 8 g, starch 1g, crude fibre 7 g, ash 4 g. Fresh leaves contain per 100 g dry matter: crude protein 19 g, ether extract 3 g, nitrogenfree extract 48 g, crude fibre 22 g, ash 9 g. Leaves are quite rich in essential amino acids, but lack the sulphur-containing ones. The leaf litter persists much longer than that of some other legumes. The litter suppresses the growth of soil bacteria and fungi and soils covered with Prosopis litter are often agriculturally poor. The weight of 1000 seeds is 35-45 g. Description A flat-topped, evergreen (sometimes deciduous) shrub or small tree with twisted stem, up to 13(-20) m tall, armed with axillary, stipular spines 1-5 cm long or unarmed. Bark rough, dull-red; inner bark yellowish. Leaves with l-2(-4) pairs ofpinnae; petiole 1-4 cm long, rachis

Prosopis juliflora (Swartz) DC. - 1, habit; 2, flowering branch; 3, flower; 4, pods.

3-14 mm long, ending in a spine 2-3 mm long; pinnae 3-11 cm long; leaflets in (6-)12-25(-29) pairs, sessile, elliptical-oblong, 6-16(-25) mm x 1.5-3(-6) mm, rounded to truncate at apex, mucronulate, usually glabrous, submembranous. Inflorescence an axillary, pendent, densely flowered, cylindrical, spiciform raceme, 5-15 cm long; flowers 4-5 mm long, yellow to creamy-brown; calyx broadly campanulate, about 1.5 mm long, teeth 5, slightly ciliate; petals 5, sharply acute, about 3 mm long, greenish-yellow, pilose within; stamens 10. Fruit a pendent, straight or slightly falcate, compressed pod, 8-29 cm x 9-17 mm x 4-8 mm, surface irregular, light yellow to brown; stipe up to 2 cm long, beak 3-7 mm long; valves thick, indehiscent, enclosing seeds in cavities when ripe. Seed broadly ovoid, 6 mm x 4 mm, brownish, embedded in a whitish, slightly sweet pulp. Growth and development In tests in Petrolina, Brazil, P. juliflora reached a height of 4 m, a diameter at breast height of 4.5 cm and a crown diameter of 5.4 m in 2 years. It normally grows to a height of about 10 m, while under very favourable conditions it may reach 20 m. In Brazil, it flowers profusely in December-February and pods are mature in February-May. In India, flowering and fruiting is from August-October. P. juliflora coppices readily. P. juliflora moderately enriches the soil with atmospheric nitrogen obtained through symbiosis with cowpea-type Rhizobium. The roots also form mycorrhizal associations with Glomus fungi. Plants with both mycorrhizal and Rhizobium associations show significantly higher nitrogen fixation rates than those lacking the mycorrhiza. Other botanical information The taxonomy of Prosopis L. is confused and in great need of a worldwide revision. P. juliflora is a highly polymorphic species and many varieties have been described. Several varieties such as var. glandulosa (Torrey) Cockerell and var. velutina (Wooton) Sargent are often considered separate species, denoted P. glandulosa Torrey (honey mesquite, in the southern United States) and P. velutina Wooton (velvet mesquite, in Mexico and Arizona, United States), respectively. Var. torreyana L. Benson is also classified as P. glandulosa Torrey var. torreyana (L. Benson) M.C.Johnston. These varieties are difficult to distinguish, having only larger leaflets and flower spikes than var. juliflora. Ecology The value of P. juliflora lies in its exceptional tolerance of drought and marginal soils. In its natural habitat in Peru, average annual rainfall ranges from 250-500 mm, but plants

PROSOPIS

bearing leaves andfruits canbefound in locations receiving as little as 50mm.An annual rainfall of about 800mmisrequired for optimal growth. Itis grown successfully on sandy soils in Brazil, inlocations with 1000 mmannual rainfall, where most vegetation remains green allyear. P. juliflora tolerates a dry season of8 months or even longer. In Peru, it is found up to 100m altitude, while elsewhere its range extends to 1500m altitude. The mean maximum temperature ofthe hottest month is 22-34°, the mean minimum temperature ofthe coldest month 14-22°. Some selections tolerate light frost. P.juliflora is tolerant of highly saline and alkaline soils. When grown experimentally on a 20 g/1 NaCl nutrient solution, it not only survived andcontinued togrow, but also continued to fix atmospheric nitrogen. Theroots are able toexclude NaCl; the NaCl content of the ash increasing much slower than that ofthe nutrient solution or soil.P.juliflora survives and even flourishes in soils more saline than 2S/m(13g/1 NaCl) ifitcan obtain water from a portion of the rootzone with lower salinity anditsroots continue toextractwater from soils with salinities greater than 2.8S/m (18 g/1NaCl). Fair growth is also obtained on poor sandy androcky soils. P. juliflora is sometimes said to dry out the soil and compete with grasses, particularly in dry years, hence in some areas (e.g. theUnited States) it isconsidered a weed. Thetree naturalizes easily in many regions, such as India andAustralia and may become a weed inhumid areas. Propagation and planting Propagation is possible byseed, root cuttings andgrafting. Establishment byseed isfeasible, although seed is difficult to extract from the pods. For small amounts, pods are cut open with a knife and seeds areremoved manually. For larger amounts, pods are kept in a damp place and allowed to degrade by fermentation, releasing the seeds. Alternatively, pods are fed to goats and the manure containing the undamaged seeds is used for sowing. Treatment of seed with concentrated sulphuric acid for 30 minutes is reported to improve germination, in other cases mechanical scarification was better. Aerial seeding is applied successfully to quickly cover remote, extensive and poorly accessible areas. In the United States, aerial seeding ofa mixture ofP.juliflora, Nicotiana glauca Graham and several Eucalyptus species is used to revegetate abandoned copper mines. It is common practice to grow plants in plastic bags in nurseries. Inoculation with Rhizobium andmycorrhizal fungi isadvantageous.

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Seedlings withstand watering with saline water up to EC 0.8-1.0 S/m, and at 18months brackish water ofEC 0.4-0.6 S/m andpH 7.0-7.85 still suffices. Spacing depends on the use of the trees. When grown for fuelwood, a spacing of 2 m x 2 m or wider is used in South America. In rangeland in association with grasses and other crops, spacing may beupto 10m x 10-15 m.When the emphasis is on pod production, the spacing used ranges from 5mx5-10m. Husbandry After planting, P.juliflora benefits from weeding around the stem. Young plants also need protection from grazing animals. For older plants little care is needed. Thinning and pruning are needed to avoid P.juliflora becoming a weed and to keep the plantation accessible. In rangeland in South America, allbutthelarge trees with a stem diameter of 30-50 cm are thinned outand the remaining trees are pruned to 30% of their canopy. The best species to grow in association with P.juliflora areCenchrus ciliaris L., Panicum maximum Jacq. andOpuntia spp.Although better growth of Opuntia and grasses under P. juliflora trees is often reported, there have been reports that the total fodder yield maybe lower than the yield from a well managed grass pasture. Diseases andpests In South America thewood sawyer insect Oncideres saga which cuts off young branches causes considerable damage. Other pests reported from South America are the Lycainid butterfly Hemiargus ramon damaging the flowers and the Lonchaeid fly Silba pendula and Bruchus beetles attacking the pods. The membracid treehopper Otinotus oneratus is reported to cause damage in India. Harvesting Firewood is generally cut in an 8-10-year cycle. Pods are either left for animals to browse orharvested manually. Prompt harvesting and processing ofpods mayalleviate Bruchus beetle attack, while delaying collection ofpods fallen on the ground may result in heavy losses. Where pods are stored for later useor marketed, manual harvesting is required. Yield Wood and pod yields strongly depend on the selection used andontheenvironment. Nodifference inyield between planted trees and coppice growth is reported. When cut in an 8-10-year cycle, a firewood plantation mayyield 50-60 t/ha; in a 15-year rotation, the expected yield is 75-100 t/ha. Podproduction starts in the third year after planting and peaks between 15and20years, provided trees arewell managed. Average annualpod yield is about 15kg per tree, but yields of 100kg

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from individual trees are also reported. An annual production of 10 t/ha is possible; the average production in the United States is 8.7 t/ha. Handling after harvest Pods are often attacked by insects and need careful storage. Traditionally, they are stored in sealed rooms or in layers alternating with layers of sand. Alternatively, they are fumigated and stored in a well ventilated room. Genetic resources and breeding Various collections exist, e.g. in the United Kingdom at the Commonwealth Forestry Institute in Oxford. Genetic variation exists between populations, e.g. in Pariba, Brazil. Selection work in Haiti found spineless, erect growing forms with unpalatable foliage. Selection is being carried out e.g. in Banthra, Lucknow, India. Most research in Asia is reported from the Indian subcontinent. Prospects P.juliflora is considered very useful for afforestation of saline and alkaline wasteland and for the production of fuelwood and dry season fodder. Its role as a rangeland tree deserves further research attention. It is suitable for stabilizing peripheral bunds around mangrove creeks used for fish culture. On the other hand, warnings are issued against introduction into new locations, as it may become weedy on good soils and in moist locations. Literature 111Burkart, A., 1976. A monograph of the genus Prosopis (Leguminosae subfam. Mimosoideae). Journal of the Arnold Arboretum 57: 219-249, 450-525. 12! Dutton, R.W., 1992. Prosopis species, aspects of their value, research and development. Proceedings of the Prosopis Symposium, University of Durham, United Kingdom, 27-31 July, 1992. International Prosopis Association, Durham, United Kingdom. 230 pp. I3l Feiger, R.S., 1979. Ancient crops for the twenty-first century. In: Ritchie, G.A. (Editor): New agricultural crops. Westview Press, Boulder, Colorado, United States, pp. 5-20. I4l Habit, M.A. & Saavedra, J.C. (Editors), 1988. The current state of knowledge on Prosopis juliflora. Second International Conference on Prosopis, 25-29 August, 1986, Recife, Brazil. Food and Agriculture Organization of the United Nations, Rome, Italy. 554 pp. 15! Hughes, C E . & Styles, B.T., 1984. Exploration and seed collection of multiple purpose dry zone trees in Central America. International Tree Crops Journal 3: 1-32. 161Jarrel, W.M. & Ross, A.V., 1984. Salt tolerance of mesquite. California Agriculture 38(10): 28. I7l Joshi, S.C., 1986. Aerial seeding for environmental conservation. Indian Forester 112: 1-5. 181 National Academy of Sciences, 1979. Trop-

ical legumes, resources for the future. National Academy of Sciences, Washington D.C., United States, pp. 153-163. I9l Wojtusik, T., Felker, P., Russell, E.J. & Benge, M.D., 1993. Cloning of erect, thornless, non-browsed nitrogen fixing trees of Haiti's principal fuelwood species (Prosopis juliflora). Agroforestry Systems 21: 293-300. L.J.G. van der Maesen &L.P.A. Oyen

Psophocarpusscandens(Endl.)Verde. Taxonl7:539(1968). LEGUMINOSAE - PAPILIONOIDEAE

2« = 18 S y n o n y m s Psophocarpus palustris auct., non Desv. (1826), P. longepedunculatus Hassk. (1842), Mucuna comorensis Vatke (1878). Vernacular n a m e s Psophocarpus (En). Indonesia: kecipir monyet (Javanese), jaat monyet (Sundanese). Origin and geographic distribution P. scandens is a native of tropical Africa and widely distributed from Cameroon to Angola and from Tanzania to Mozambique and Madagascar. It is cultivated in Zaire, Brazil, the West Indies, India, Sri Lanka, Burma (Myanmar), Vietnam and Indonesia. It has naturalized in Brazil. Uses P. scandens is grown as a cover crop and green manure in Central Africa, Asia and tropical parts of the New World. In Indonesia, it is grown as a cover crop in rubber and oil-palm plantations, while the leaves are used as a fodder in a mix with grasses and other legumes. In West Africa, the pods are used as a famine food. In Zaire, the primary use is as a vegetable; in the market of Kinshasa, Zaire, bundles ofyoung shoots and pods are sold and eaten after boiling in water or milk. The pods are given to nursing mothers to stimulate milk production. In Zaire, it is also grown as a fodder for livestock and for fish raised in ponds. In traditional medicine, bruised leaves are applied as a compress for open cuts, wounds, and haemorrhoids. Fresh and dried leaves are consumed after boiling or as a tea to relieve the discomfort of stomach inflammations. In Zaire, P. scandens is also a source of tannin. Properties In Indonesia, immature pods of P. scandens contain per 100 g: 88-95 g water and 1.2-3.1g protein. In Zaire, foliar analyses indicated per 100 g dry matter: protein 31-39 g, lipids 12 g, carbohydrates 32 g, P 0.35 g, K 1.2 g, Ca 2.1-3.1 g, Mg 0.4-1.4 g, S 0.5 g; analyses ofpods indicated per 100 g dry matter: protein 7.1-27.9 g, lipids 2.7

PSOPHOCARPUS

g, carbohydrates 56.4 g, P 0.1-0.5 g, Ca 0.5-2.3 g, Mg 0.1-1.5 g. Analyses of the leaves in Sumatra (Indonesia) indicated per 100 g dry matter: C 25.9 g, N 4.5 g, P 0.26 g, K 1.0 g, Ca 1.3 g, Mg 0.3 g; analysis of the stems indicated per 100 g dry matter: C 27.2 g, N 1.85 g, P 0.14 g, K 1.6 g, Ca 1.1 g, Mg 0.3 g; analysis of the roots: C 27.5-30.6 g, N 2.3-2.4 g, P 0.2 g, K 0.8-1.0 g, Ca 1.0-1.3 g, and Mg 0.2 g. The protein content ofthe seed is higher than in other legumes, except for groundnut, soya bean and winged bean. P. scandens produces a nectar that is rich in sucrose from glands in the flowers and on the pedicels. The weight of 1000 seeds is 90-100 g. Description Perennial climbing or twining herb, 1-6 m long, with a tuberous main root and glabrous or sparsely hairy to glabrous stems. Leaves trifoliolate; stipules oblong-lanceolate, persistent, spurred, 0.8-1.7 cm long including the spur; petiole 5-18 cm long; rachis 0.8-5 cm long; petiolule 3-6 mm long; leaflets ovate-rhomboid to broadly rounded, 2.5-12 cm x 1.8-10 cm, acute or

Psophocarpus scandens (Endl.) Verde. - 1, flowering branch; 2, stipules; 3, bracteole; 4, standard; 5, stigma; 6,pod; 7,seed.

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acuminate at the apex, cuneate to truncate at the base, occasionally 3-lobed, glabrous or glabrescent on both surfaces, margin often ciliate. Inflorescence a several to many-flowered pseudo-raceme; peduncle 3-40 cm long; rachis 5-12 cm long, pubescent; pedicel 2-6 mm long, pubescent; bracts semi-caducous, ovate-lanceolate or elliptical, 5-11 mm x 2-4 mm; bracteoles persistent, ovate-oblong or elliptical, 7-14 mm x 5-8 mm, nearly as long as or longer than the calyx, glabrous or glabrescent; calyx glabrous or puberulous, tube 5-7 mm long, lower lip with median triangular lobe 2.5-3.5 mm long, and 2 lateral very broadly deltoid lobes 1.5 mm long, 2 upper lobes fused into an emarginate lip; standard pale-blue or mauve, obovate-oblong, 1.5-2.1 cm x 1.2-1.5 cm, emarginate; wings bluelilac or with blue or violet margin; keel 5.5-7 mm wide, blue-lilac, whitish or with blue or violet margin, not prominently beaked. Fruit an oblong pod, square in cross-section, 3.5-8 cm x 6-7 mm, 4-8-seeded, glabrous, prominently 4-winged, wings 2.5-6.5 mm wide, slightly serrate, often striate, sometimes puberulous along the margins. Seed oblong or sub-cylindrical, (5-)6-7.5 mm x (3.5-)5-6 mm, blackish-purple, with minute granular, orange, easily removable tomentum or brown silky hairs on the edges. Seedling with epigeal germination, first leaves blotched. Growth and development After germination, initial growth is slow; once well established, growth is vigorous. When grown mixed with other cover crops, P. scandens may overgrow and suppress the companion crops within a year, remaining as the sole cover crop after two years. Planted as a ground cover, the ends of the shoots rise and twine. In dense stands, they may find mutual support and intertwine, forming loose strands or conical heaps rising well above the rest of the cover crop. These heaps become top-heavy, bend and are then taken up in the cover crop. The sprouts of new shoots may form similar heaps which intermingle with the older ones forming an airy, but closed soil cover. Branches may root at the nodes where they touch the soil. Nodules with abundant leghaemoglobin may form on these adventitious roots. In Sumatra, flowering starts about 115 days after sowing, taking place from January to March, while fruits mature from April to May. Some further flowering and fruiting may take place from October to December. In Hawaii, flowers are initiated during late October and early November and flowering continues until mid-February to early March. Seed can be collected from plants any time

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ofthe year since pod shattering is low in humid locations. In Bogor (Indonesia), bumble bees (Xylocopa confusa) have been observed to visit open flowers. Only the lower flowers in an inflorescence usually develop into fruits; the upper flower buds abort unless the lower ones are damaged. Other botanical information P. scandens used to be included in P. palustris Desv. and is still often confounded with it. Most agronomic information on P. palustris should be attributed to P. scandens. P.palustris is restricted to Africa, occurring from Senegal to the Sudan. It differs from P. scandens in the following characteristics: is a pubescent herb; leaflets ovate-elliptical, never 3lobed, terminal leaflet broadest in the middle, with cordate base; bracteole 4.5-6.5 mm x 3-5 mm, approximately half the length of the calyx; keel beaked at apex, 6.5-9 mm wide; pod 2.3-5.5 cm long, 3-5-seeded. P. scandens is sparsely pubescent to glabrous; leaves ovate, occasionally 3lobed, terminal leaflet broadest near the base, base more truncate; bracteole 7-14 mm x 5-8 mm, equal in length or longer than the calyx; keel not prominently beaked, 5.5-7 mm wide; pod 3.5-8 cm long, 4-8-seeded. P. palustris also differs from P. scandens in having a chromosome number of In = 22. At the edges of their natural areas of distribution some introgression occurs. A few specimens show bracteole characteristics of P. palustris and leaflet characteristics ofP. scandens. Ecology In Zaire, P. scandens grows well in locations with average annual rainfall of 1200-1800 mm, and mean annual temperature of 25°C. It thrives in full sunlight, but tolerates some shade. It prefers damp sites near lakes, marshes, ponds, rivers and streams, but also occurs in drier environments. It is found in disturbed habitats such as grassland, fallow land, riverine thickets, savanna edges, in periodically flooded forest, swamp forest edges, semi-deciduous forest and secondary forest up to 950 m altitude. It grows well on heavy, swamp soils. In East Java, it is grown on gley soils of low humus content, with a loamy-clay texture. Propagation and planting P. scandens is propagated by seed, but vegetative propagation by cuttings or tuberous main roots is also possible. Stem and root cuttings may be successful, if rainfall is sufficient, but they require much labour. After harvesting, the germination rate of the seed declines rapidly; only 15% of seeds stored in gunny-bags will germinate after 3 months' storage. Seed can best be stored in the pod in a ventilated room where pods can be fumigated regularly. In

this way about 90% ofthe seed remains viable and germinates after 6 months' storage. In Sumatra, seed matures during the dry season and can be sown in the field in the subsequent short rainy season. This requires adequate rainfall during the germination stage. Alternatively, seed is sown in nurseries, requiring daily watering for 1 month. Seedlings may then be transferred to polythene bags and can be planted out in the field after 1-2 months. Transplanting is preferably done at the beginning ofthe main rainy season. As a sole crop, a planting distance of 75 cm between rows is commonly practised, needing about 25 kg seed per ha. Husbandry Intensive and frequent weeding is necessary until the crop cover closes.A sole crop of P. scandens may cover the ground in 8-16 months after planting. It requires plenty ofwater and may compete with the main crop during the dry season. When interplanted between rubber trees, rubber yields were found to increase by up to about 165%. It is better to sow a mixed cover crop of P. scandens, Calopogonium mucunoides Desv., Centrosema pubescens Benth. and Pueraria phaseoloides (Roxb.) Benth. than to sow a sole crop, as the mixture may cover the soil already in 4 months after planting and may persist for several years. Once established, P. scandens competes well with weeds and suppresses Imperata cylindrica (L.) Raeuschel under high rainfall conditions. A sole cover crop of P. scandens may reach fresh weight yields per ha of approximately 4.6 t leaves, 11.3 t stems, 1.85 t roots, and 15 t litter. In Nigeria, P. scandens has been tested as a permanent cover crop, interplanted with maize. Maize planted in cleared strips in between the cover crop gave higher yields than zero tillage planting or conventional tillage. Applying N fertilizer increased yields; the highest maize yield (2.6 t/ha) was obtained with a P.scandens cover and an application of 60 kg N per ha. After 5 years, the cover crop was ploughed in and maize was sown, yielding 3.9 t/ha. This was almost double the yield of the best, conventionally planted, fertilized treatment. Diseases and pests P. scandens is generally little affected by diseases and pests. It is resistant to several diseases and pests affecting the closely related P. tetragonolobus (L.) DC. such as false rust (Synchytrium psophocarpi), yellow mosaic virus, leaf spot and leaf curl. It is also less susceptible to necrotic mosaic and flower blight. The nematode Heterodera marioni attacks P. scandens in Sumatra (Indonesia) and Mauritius.

PUERARIA

In Zaire, weevils (Bruchidae) attack the seed. Genetic resources Strains of P. scandens are available at the International Institute of Tropical Agriculture, Ibadan, Nigeria and from the Southern Regional Plant Introduction Station, Griffin, Georgia, the United States. Breeding Efforts to cross P. scandens with P. tetragonolobus which has the same chromosome number, using P. tetragonolobus as the female or male parent, have failed, probably because of differences in karyotype. If interspecific hybrids can be obtained, they will probably be sterile, so it will not be easy to transfer genes for disease and pest resistance from P. scandens to P. tetragonolobus. Prospects P. scandens is a useful cover crop in humid areas, especially in rubber plantations; it deserves wider attention. Because ofthe very high protein content of the leaves, it may be a useful fodder grown as a component in pastures or as a sole crop. More research is needed on propagation, husbandry, and breeding. Literature 11! Citroreksoko, P.B., 1977. Kandungan protein jenis-jenis Psophocarpus di Jawa, Madura dan Bali [Protein contents of Psophocarpus species in Java, Madura and Bali]. Berita Biologi 2(1): 23-24. 121 Gunasekera, S.A., Shanthichandra, W.K.N. & Price, T.V., 1990. Disease incidence, severity and pod yield of winged bean (Psophocarpus tetragonolobus) accessions and Psophocarpus scandens. Tropical Pest Management 36(3): 207-210. I3l Harder, D., Lolema, O.P.M. & Tshisand, M., 1990. Uses, nutritional composition, and ecogeography of four species of Psophocarpus (Fabaceae, Phaseoleae) in Zaire. Economic Botany 44(3): 391-409. 141 Mangoensoekardjo, S. & Soewadji, R.M., 1977. Pengaruh penutup tanah terhadap tanaman karet III. Ditinjau dari segi hasil [The influence of ground covers on rubber. III. Effect on yield]. Bulletin Balai Penelitian Perkebunan (BPP) Medan 8(4): 117124. 151 Mehra, K.L., Wulijarni-Soetjipto, N. & Soepardiyono, E.K., 1985. Indonesian economic plant resources: legume and other forage plants. Lembaga Biologi Nasional-LIPI, Bogor, Indonesia, p. 30. 161Mulongoy, K. & Akobundu, I.O., 1992. Agronomic and economic benefits of N contributions by legumes in live-mulch and alley cropping systems. International Institute of Tropical Agriculture (UTA) Research 4: 12-16. I7l Pickersgill, B., 1980. Cytology of two species of winged bean, Psophocarpus tetragonolobus (L.) DC. and P. scandens (Endl.) Verde. (Leguminosae). Botanical Journal of the Linnean Society 80: 279-291. I8l

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Sastrapradja, S., Lubis, S.H.A., Lubis, I. & Sastrapradja, D., 1978. A survey of variation in Psophocarpus tetragonolobus (L.) DC. with reference to the Javanese samples. Annales Bogorienses 6(4): 221-230. I9l Tong, T.H., Tjong, J.K. & Lubis, I.P., 1961. Psophocarpus palustris - an ideal ground cover for oil palm and rubber. Proceedings of the National Rubber Research Conference, 26 September - 1October 1960, Kuala Lumpur. Rubber Research Institute of Malaysia, Kuala Lumpur, Malysia. pp. 312-324. llOl Verdcourt, B. & Halliday, P., 1978. A revision of Psophocarpus (Leguminosae-Papilionoideae-Phaseoleae). Kew Bulletin 33: 191-227. N. Wulijarni-Soetjipto

Pueraria phaseoloides (Roxb.) Benth. Journ. Linn. Soc. 9: 125 (1865). LEGUMINOSAE - PAPILIONOIDEAE

In =22, 24 Synonyms Dolichos phaseoloides Roxb. (1832). Vernacular n a m e s Tropical kudzu, puero (Australia) (En). Kudzu tropical, puero (Fr). Indonesia: kacang ruji, krandang (Javanese), fuo banga (Ternate). Malaysia: kacang hijau hutan, tampong urat. Philippines: singkamasaso (Tagalog), bahay (Bikol), vaay (Ivatan). Burma (Myanmar): pe ying pin. Laos: pièd, s'üak pied. Thailand: thua-sianpa (central). Vietnam: d[aa]u ma, d[aa]u dai, d[aa]u r[uf]ng. Origin and geographic distribution Tropical kudzu is indigenous to the lowlands of East and South-East Asia where it occurs on river banks and roadsides, fallow fields and young secondary forest. It has been introduced into other tropical regions and is now cultivated and naturalized throughout the wet tropics. Uses Tropical kudzu is especially important as a component of grazed and ungrazed cover crop mixtures in rubber, oil-palm and coconut plantations in South-East Asia, Africa and tropical America. In East Africa, it is grown as a cover crop in plantations of sisal (Agave sisalana Perrine). In South-East Asia, tropical America and Australia it is also used as a pasture legume. Its ability to smother weeds makes it a useful pioneer legume often grown in combination with other more permanent species. It is planted on sloping sites to control soil erosion and in rotation with annual crops as a green manure. The tuberous roots are edible. Strong fibres from the stem are used for rope making. In Malesia, the

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plant is used in traditional medicine to cure boils and ulcers. Properties Chemical analysis of a pure tropical kudzu cover crop under oil palm grown on a Selangor-series soil in Malaysia, producing a living biomass of 4.9 t/ha dry matter in 18 months, indicated a nutrient content per 100 g dry matter of: N 2.35 g, P 0.20 g, K 2.14 g, Mg 0.20 g.A similar cover on a Serdang-series soil in Malaysia produced a living biomass of 5.8 t/ha dry matter in 12 months, containing per 100 g: N 3.01 g, P 0.32 g, K 2.02 g, Mg 0.14 g. Litter of tropical kudzu decomposes fairly slowly. In a litterbag experiment in Colombia at an average temperature of 26°C, the halflife of organic matter was about 110 days during the rainy season and 220 days during the dry season. On average, about 75% of K was leached out ofthe litter after 1month, while the concentration of N and P in the remaining litter was approximately constant. Tropical kudzu is very palatable, although its wetseason palatability is reported to be low in tropical America. Nutrient concentrations typically range from 2-4% N, 30-40% crude fibre, 0.15-0.45% P and 0.4-1.6% Ca. The weight of 1000 seeds is 10-12 g. Description Deep-rooting perennial herb with climbing or twining, hairy stems. Roots subtuberous. Main stems about 6 mm in diameter, extending 4.5-10 m, rooting at nodes if in contact with moist soil, lateral stems branching from nodes; young shoots densely covered with brown hairs. Leaves large, trifoliolate; stipules triangular to ovate, 4-11 mm x 2-3 mm, pubescent; petiole 3-11 cm long, hairy; stipels lanceolate to setaceous, 3-7 mm long; petiolule 2-5 mm long; top leaflet symmetrical, triangular or ovate, 2-20 cm x 2-16 cm, thin, base broadly cuneate or subrhomboidal and very shallowly lobed, apex acuminate, lateral leaflets oblique, (4-)6-7(-14) cm x (3-)6-7(-12) cm, thinly hairy on upper surface, greyish-green and densely pubescent on lower surface. Inflorescence an axillary, unbranched raceme, 10-46 cm long, pubescent; peduncle about 13cm long; bracts 2-5 mm long, pubescent; flowers 10-23 mm long, mauve to deep purple, borne in pairs; bracteoles lanceolate, 1-3 mm long; pedicel 2-6 mm long; calyx campanulate, 6 mm long, hairy, upper teeth broad, lateral ones triangular, the lower lanceolate and all terminating in a bristle; standard orbicular, 1-2.5 cm in diameter, spurred, greenish on outside and white on the inner side with a mauve violet central blotch; stamens 10, diadelphous. Fruit a straight or slightly curved, terete or

Pueraria phaseoloides (Roxb.) Benth. - 1, flowering branch; 2, flower, frontal and side view; 3, pod; 4, seeds. compressed cylindrical pod, 4-12.5 cm x 3-5 mm, thinly clothed with stiff appressed hairs, black when mature, 10-20-seeded. Seed cylindrical to cubic with rounded corners, about 3 mm x 2 mm, brown to brownish-black. Growth and development Seedling growth of tropical kudzu is only moderately vigorous during the first 3-4 months. Seedling vigour is superior to other cover crops such as centro (Centrosema pubescens Benth.) and calopo (Calopogonium mucunoides Desv.). Once established, it is very vigorous and quickly smothers weeds. Unless regularly controlled, it tends to climb the stems of trees and to get entangled in the fronds of young palms. In Malaysia, it reaches 60-70% cover after about 4 months and 90-100% after 8 months. It can form a tangled mat of vegetation 60-75 cm deep. Flowering in Java is from May to October. Other botanical information Three botanical varieties are distinguished within P. phaseoloides: - var. javanica (Benth.) Baker (synonym: Puerariajavanica (Benth.) Benth.): leaflets mostly entire, rarely somewhat lobed; flowers 15-23 mm long; bracts and calyx pubescent, lateral calyx

PUERARIA

lobes obtuse, lower calyx lobe acute; fruit 7-11 cm x 4-5 mm. Worldwide it is the most common variety, also introduced into tropical Africa and America. Its most probable origin is in Java and Peninsular Malaysia. - var. phaseoloides: leaflets entire, lobed or sinuate; flowers 7-15 mm long; bracts and calyx short-pubescent, lateral calyx lobes acute, lower calyx lobe acuminate-lanceolate; fruit 5-9 cm x 3-4 mm. It occurs mainly in South and SouthEast Asia. Its most probable origin is in southeastern China. - var. subspicata (Benth.) van der Maesen (synonym: Pueraria subspicata (Benth.) Benth.): leaflets large, entire to deeply lobed; flowers 15-23 mm long; bracts and calyx densely longpubescent, lateral calyx lobes acute, lower calyx lobe lanceolate-subulate; fruit 7-12.5 cm x 4-5 mm. It occurs mainly in India, Bangladesh, Burma (Myanmar) and Thailand. Its most probable origin is in north-eastern India. The ecological requirements of the 3 varieties are the same. Sometimes overlapping morphological characteristics occur. Named cultivars exist in South America and Tanzania, but seed is mostly traded without cultivar name. Ecology Tropical kudzu is best suited to the humid lowland tropics up to 1000 m altitude with an annual rainfall in excess of 1500 mm. In an experiment under controlled conditions, an optimum temperature of 32/24°C (day/night) was found and dry matter yields were reduced by 35% with a change in temperature regime to 26/15°C. Few reports are available on photoperiod responses. In Puerto Rico (latitude 18°N), flowering and seed set occur in the short daylength period from January to March, suggesting that it may be a shortday plant. In Papua New Guinea and Africa, it only sets seed under dry conditions. In comparison with other legume species tropical kudzu has been ranked highly as a shade-tolerant plant. When grown under 50% shade in coconut plantations in the Solomon Islands it was the most productive legume and it even suppressed the accompanying grasses. This characteristic makes it suitable in integrated livestock/plantation production systems. Under a regime of more than 50% shade, tropical kudzu is still comparatively productive, but in mixtures it gives way to other species like centro (Centrosema pubescens) or desmodium (Desmodium heterocarpon (L.) DC. subsp. ovalifolium (Prain) Ohashi). Tropical kudzu is tolerant of very wet and waterlogged sites. It prefers heavy soils and is well

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adapted to acid soils. It is particularly susceptible to Mg and S deficiencies and has moderate to low Ca and P requirements, but it responds to fertilizer application. On poor oxisols and ultisols P. phaseoloides also requires K and Mg fertilizer. It is not tolerant of salinity. Propagation and planting Tropical kudzu is usually established from seed. Having a high proportion ofhard seed, germination can be increased by hot water, acid or mechanical scarification. Commercially available seed is often scarified by abrading the seed-coat in a hexagonal drum, lined with sandpaper, rotating at 7.5 rpm for 24 hours. Tropical kudzu usually nodulates with native cowpea rhizobia but inoculation with an appropriate strain of Bradyrhizobium, such as RRIM 768 in Malaysia, is recommended for new areas. Seed is usually broadcast or drilled in rows 1 m apart. It can also be established by oversowing into an existing pasture if the pasture is disked or burnt beforehand. When seed is scarce, tropical kudzu can be propagated vegetatively, one recommendation being to plant two rooted cuttings, 0.7-1 m long, at each point on a 1-2 m grid. In Africa, a tropical kudzu cover can sometimes be established by selectively weeding the natural regrowth after land clearance. Standard seed mixtures for cover crop contain a 5:4:1 ratio of calopo, centro and tropical kudzu or a 4:1 mixture of centro and tropical kudzu. Seeding rates for these mixtures are 5-10 kg/ha in the inter-row areas between rubber or oilpalm trees. Husbandry When planted under palm and other tree crops on former forest land, some initial control of natural regrowth of forest plants is necessary to establish tropical kudzu. Manual weeding gives the best results, but several herbicides have been used successfully (e.g. oxyfluorfen as a post-emergence herbicide at 0.5 kg/ha). During the subsequent two years, tropical kudzu has to be cutlassed or beaten down to a height of30 cm. Circles around trees are clean-weeded to prevent tropical kudzu from climbing the trees. In sisal plantations in East Africa its vigour is reduced by low rainfall (800 mm) which checks its climbing habit. It competes with oil palm for moisture during dry periods and it has been recommended to check the growth of tropical kudzu at the start of the dry season. The largest effect oftropical kudzu on associated tree crops occurs when it dies off 3-4 years after planting. Marked increases in tree growth and rubber yield are found during that period, not during the first 3 years. Tropical kudzu responds well to added P; linear responses to up to

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50kg/ha ofP have been obtained on infertile soil. Tropical kudzu is very palatable to animals and this can lead to selective grazing and poor persistence. Grazing experiments in Malaysia have shown that under continuous grazing at stocking rates of 2-6 head oflocal cattle per ha, the proportion of tropical kudzu was significantly reduced with increased stocking even after one year of grazing. Farmers using grass-legume mixtures have also reported excellent growth of tropical kudzu in the first two years, and rapid decline under grazing. The lack of persistence of tropical kudzu is probably also influenced by physical soil characteristics and related to the poor development ofrooted stolons on some soils. Diseases and pests Tropical kudzu is remarkably free from diseases, although leaf-eating caterpillars can damage ungrazed swards and pod-borers reduce seed production. Harvesting Tropical kudzu is usually directly grazed in mixed pastures but can be cut for hay, silage or for feeding as fresh forage. Yield Annual dry matter yields of up to 10 t/ha from tropical kudzu swards have been recorded in cutting experiments, with some 65-75% of the yield from the wet season and 25-35% from the dry season. Dry matter yields ofup to 23 t/ha have been measured in tropical kudzu-grass swards, 40% of this being tropical kudzu. In tropical America, tropical kudzu-grass pastures have produced live weight gains of 313 kg/ha per year (with Andropogon gayanus Kunth) and 542 kg/ha per year (withPanicum maximum Jacq.) Genetic resources and breeding The largest germplasm collection is maintained by the Centro Internacional de Agricultura Tropical (CIAT), Colombia and a smaller collection is held at the Australian Tropical Forage Genetic Resource Centre (ATFGRC), CSIRO, Australia. There are no known breeding programmes with tropical kudzu in South-East Asia. Prospects Tropical kudzu is, and will probably remain, the most widely grown cover crop throughout the humid tropics, especially in tree plantations. Its main features as a forage legume are its vigorous initial growth on fertile soils and its high palatability. Improvements should primarily be aimed at improving its persistence under grazing. Literature 111 Chin, S.L., 1977. Leguminous cover crops for rubber smallholdings. Planters' Bulletin 150: 83-97. I2l Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp.

214-216. 131Eng, P.K., Chen, C.P. & 't Mannetje, L., 1978. Effects of phosphorus and stocking rate on pasture and animal production from a guinea grass legume pasture in Johore, Malaysia. 2. Animal live weight change. Tropical Grasslands 12: 198-207. 141 Han, K.J. &Chew, P.S., 1982. Growth and nutrient contents of leguminous covers in oil palm plantations in Malaysia. In: Pushparadja, E. & Chew, P.S. (Editors): The oil palm in agriculture in the eighties. Vol. 2. Incorporated Society of Planters, Kuala Lumpur, Malaysia, pp. 235-251. 151 Hardjono, A. &Warsito, T., 1989. Respon tanaman penutup tanah campuran (Calopogonium mucunoides + Centrosema pubescens + Pueraria phaseoloides) terhadap pengapuran. 2. Percobaan lapangan [Response of a mixed cover crop (Calopogonium mucunoides + Centrosema pubescens + Pueraria phaseoloides) to liming. 2. Field experiment]. Menara Perkebunan 57: 19-23. 161 Skerman, P.J., Cameron, D.G. & Riveros, F., 1988. Tropical forage legumes. 2nd Edition. FAO Plant Production and Protection Series No 2. Food and Agriculture Organization of the United Nations, Rome, Italy, pp. 376-388. I7l Thomas, R.J. & Asakawa, N.M., 1993. Decomposition of leaf litter from tropical forage grasses and legumes. Soil Biology and Biochemistry 25: 1351-1361. I8l van der Maesen, L.J.G., 1985. Revision of the genus Pueraria DC. with some notes on Teyleria Backer. Agricultural University Wageningen Papers 85-1, Wageningen, the Netherlands, pp. 71-88. I9l Wong, C.C., 1990. Mineral composition and nutritive value oftropical forage legumes as affected by shade. MARDI (Malaysian Agricultural Research and Development Institute) Journal 18:125-143. R.A. Halim

Rhizophora apiculata Blume Enum. pi. Javae 1:91 (1827). RHIZOPHORACEAE

2« = 36 Synonyms Rhizophora candelaria DC. (1828), R. conjugata Arnott (1838), non L. (1753). Vernacular n a m e s Brunei: bakau minyak, bakau. Indonesia: bakau minyak (general), bako (Javanese), babakoan laut (Sundanese). Malaysia: bakau minyak, bakau tandok, bakau akik. Papua New Guinea: abia (Gulf Province), bahkweh (Northern Province), pana (Central Province). Philippines: bakauan (lalaki), uakatan (Tagalog), bakhau (Samar). Singapore: bakau minyak, redtree. Burma (Myanmar): pyoo. Cambodia: kaông

RHIZOPHORA

ka:ng nhi:. Thailand: kongkang-bailek, kongkang. Vietnam: c[aa]y d[uw][ows]c. Origin and geographic distribution R. apiculata is commonly found in most mangrove swamps in tropical Asia, from the delta of the Indus in Pakistan to Vietnam and Hainan. It occurs throughout the Malesian region and reaches southwards to the Tropic of Capricorn in Queensland, and eastwards as far as New Caledonia and Ponape (Micronesia). Uses The wood ofR. apiculata can be split easily and has a high energy value, making it in great demand as firewood and for making charcoal. In recent years it has been extensively harvested for production of wood chips in East Malaysia and Indonesia. R. apiculata is the preferred species in replanting programmes in most mangrove regions in South-East Asia. Poles are used for piling and construction purposes, and as fishing stakes. The timber is suitable for making furniture. The branched stilt roots weighted with stones serve as anchors. The bark is rich in tannin, used for tanning leather and to toughen and dye fishing lines, ropes and nets. The bark provides a medicine against dysentery. Rhizophora hypocotyls can be eaten after extraction of the tannin, but this is probably only of importance in times of famine. Production and international trade In all parts oftropical Asia, R. apiculata is cultivated on a commercial scale for production of firewood and particularly charcoal, poles and tannin. Few production statistics from natural or planted stands are available. In Vietnam, annual wood production is about 60 000 t. Properties The energy value of the stems, branches and prop roots is 15 000-19 000 kJ/kg, of charcoal 32 200 kJ/kg. The ash content is about 1 g per 100 g wood ofthe stem and prop roots, and 2 g in branch wood. Leaf samples in the Matang Mangrove Forest which consists of almost pure stands of R. apiculata contain per 100 g dry matter: N 0.4-1 g, P 0.1 g, K 0.9-1.2 g, Ca 1.1-2.0 g, Mg 0.4-0.8 g, Na 1.6-1.9 g. The quantity of tannin in the bark is very variable, 8-40% in air-dried bark. The tannin ofRhizophora is associated with a substance which darkens gradually; it is used as a deep brown or black dye. The bark, according to some analyses, contains large quantities of pentosans and furfurol. After extraction of the tannins, the ash mainly consists of calcium carbonate (70%) and lime (18%) and can be used as fertilizer. The wood of R. apiculata is hard, strong and heavy with an air-dry density of 960-1170 kg/m 3 .

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The sapwood is light yellow, 3-5 cm thick, and very distinct from the heartwood which is reddishbrown and darkens with age. Growth rings and parenchyma are indistinct. Pores are small, circular, fairly numerous, straight, solitary and in short radial groups, mostly in pairs, and frequently with dark gummy deposits. Rays are numerous, straight, forming conspicuous silvery grains, narrower than the pores, and visible to the naked eye. Description Evergreen tree, up to over 30 m tall and with trunk up to 50 cm in diameter, generally much smaller in exploited forests; bole 10-12 m; stem supported by numerous, lateral, much branched stilt roots; aerial roots sometimes develop from the lower branches; taproot usually abortive; branching primarily sympodial. Bark grey, almost smooth or with vertical fissures. Branchlets swollen at the nodes, solid and pithy. Leaves decussate, rosette-like at the end of twigs; stipules lanceolate, 4-8 cm long, conspicuous, caducous; petiole 1.5-3 cm long, reddish; blade entire, elliptical-oblong to sublanceolate, 7-18 cm x

Rhizophora apiculata Blume - 1, habit; 2, leafy branch with flowers and seedling fruits; 3, pair of flower buds; 4,flower; 5,fruit with seedling.

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3-8 cm, leathery, green and shiny, apex acute to apiculate, base cuneate, veins distinct above, obscure beneath, glabrous with minute, scattered black corky warts on the lower surface, visible on older or dried leaves. Inflorescence axillary (in leaf scar below the leaf rosette), 2-flowered; peduncle thick, 0.5-1.5 cm long; bracteoles at the base of flower, cup-shaped, fleshy, crenulate; flowers bisexual, sessile, yellow; calyx deeply 4-lobed, coriaceous, accrescent and reflexed in fruit, lobes ovate, 10-14 mm x 6-8 mm, concave, acute, brown-yellow to reddish, persistent; receptacle with a disk; petals 4, free, lanceolate, 8-11 mm x 1.5-2 mm, membranous, glabrous, early caducous; stamens mostly 12, sessile, anthers 6-7.5 mm long, acute, multi-loculate, opening with a large ventral valve; ovary semi-inferior, 2-celled, superior part enclosed by the disk, bluntly conical, 1.5-3.5 mm long; style 0.5-1 mm long, 2-lobed. Fruit an ovoid or inversely pear-shaped berry, 2-3.5 cm long, rather rough, brown. Hypocotyl cylindrical to club-shaped, up to 40 cm x 1.2 cm before falling, often slightly curved, more or less blunt, smooth and shining, green tinged with red. Growth and development The stem of R. apiculata is upright and cylindrical in closed forest, but plants develop a straggling or semi-prostrate habit in unfavourable sites. Flowers are selfcompatible and usually wind-pollinated. Insects have occasionally been observed foraging for pollen. Vivipary is characteristic for Rhizophora species. One-seeded fruits start to germinate when still hanging on the tree. The root protrudes from the fruit, producing a green, spindle-shaped rod (hypocotyl) of up to 40 cm long. Eventually, the seedling falls from the fruit, floats with the high tide and establishes if it reaches a suitable site. Seedlings may retain their viability for several months. Average annual increase in diameter over a 30year period in Matang, Malaysia, was 0.32 cm. Litterfall varies with stand vigour and age. Estimates ofannual litterfall vary from 6-11.5 t/ha. Other botanical information In South-East Asia 3 Rhizophora species occur: R. apiculata, R. mucronata Poiret and R. stylosa Griffith. R. apiculata is slightly more common than R. mucronata to which it is closely related. They can be distinguished in the field by some easily observed characters: bark grey, almost smooth, with vertical fissures in R. apiculata; in R. mucronata the bark is nearly black or reddish, rough or sometimes scaly. Inflorescence in R. mucronata longer, forked 2 or 3 times, with more numerous flowers; hypocotyl

longer (35-65(-90) cm). R. stylosa has broadly elliptical leaf blades, up to 12 cm x 7 cm, flowers with styles 4-6 mm long and the hypocotyl up to 30 cm long. A few specimens have been collected with characters intermediate between R. apiculata, R. mucronata and R. stylosa in western Malesia and western New Guinea. Ecology R. apiculata is the most common mangrove species. It grows gregariously in swamps flooded by normal high tide, on deep soft mud of estuaries, often consolidated and sheltered from surf and currents by pioneer species of Avicennia L. and Sonneratia L.f. R. apiculata avoids hard soils and develops well in per-humid regions where it can form almost pure stands, sometimes in association with Bruguiera spp. or R. mucronata. It does not occur in fresh water swamps. It is killed by frost and by extended periods of nearfreezing temperatures. Propagation and planting The best way to regenerate a mangrove stand at the least cost is to encourage reproduction in the period before the final harvest by thinning and by minimizing damage to young plants during harvesting. Damaged young trees are capable ofrecovering by sprouting from dormant buds and bending upwards to form another erect stem. Additional planting and planting in denuded areas mostly succeeds well, provided the ecological conditions are suitable. Natural regeneration is often good, provided sufficient seed trees are left after harvesting. In nurseries shade is neither advantageous nor harmful. Seedlings tend to be taller in shade and produce fewer roots. Planting programmes often coincide with the fruiting season. Mature propagules that remain viable for 4-5 months are gathered from the forest floor. The planting procedure is simple, involving inserting the propagules vertically into the muddy soil along predetermined lines and spacings. In sites where attempts at planting had previously failed due to pest problems, planting nurseryraised seedlings and transplanting of wildings proved successful. Wildings are readily available, as natural regeneration is often profuse. More intensive site preparation is required where flooding is limited due to large numbers of crab mounds and where there is severe infestation of Acrostichum ferns. Husbandry In Peninsular Malaysia it takes 35 years for R. apiculata to reach a stem diameter of 19 cm at breast height. Judging by the greatest volume production of firewood, a 40-year rotation is preferable. Current rotations vary from 15

RHIZOPHORA

years (in firewood plantations in Thailand) to 20-30 years, but may be even shorter. Thinning is important for good stand development. Three thinnings are prescribed in Matang, Malaysia (at 15, 20, and 25 years of age), one thinning in Indonesia. In practice, thinning is irregular, incomplete and selective, and poorly accessible stands are often neglected. As thinning is a commercial operation, its timing, as well as the selection of tree species and stem diameter are influenced by market demand. Diseases and pests Propagules of Rhizophora spp. are sometimes attacked by a scolytid beetle (Poecilips fallax). Occasionally, bagworms and larvae of the moth Strelote lipara cause localized defoliation of trees and seedlings. In some plantations, long-tailed macaques (Macaca fascularis) and grapsid crabs (Sesarma spp.) have been reported to be the major pests of newly planted propagules. The ferns Acrostichum aureum L. and A. speciosum Willd. may occur throughout South-East Asia as a low, tufted ground cover under the canopy. With the opening of the canopy, the ferns may form up to 4 m tall, dense, continuous thickets, making it impossible for propagules of Rhizophora to enter the area. Large areas of formerly productive Rhizophora stands have been made unproductive in this way. Uprooting the ferns manually with iron bars or spraying with a herbicide can solve the problem, unless the inundation regime has changed. Derris trifoliata Loureiro can also be a serious strangling weed. Harvesting Felling of R. apiculata for poles is essentially a thinning operation in which straight pole-sized individuals are cut. If cut at least 20 cm above the stilt roots, regeneration is without problems. The poles are carried out of the swamp. In Malaysia, stick thinning is practised. This process involves selecting a well-formed tree and felling all pole-sized trees around it within a radius drawn by a stick 1.2-1.8 m long. The system of final harvesting of trees for fuelwood varies between countries. Thailand and Indonesia adopt strip-felling, the Philippines and East Malaysia practise minimum diameter harvesting, while clear-felling has been traditionally carried out in Peninsular Malaysia. Minimum diameter for charcoal production varies from 20.5 cm in Sabah to 4 cm in Vietnam. Felled trees are bucked into billets of about 1m long, and sometimes debarked before they are transported out of the swamp forest. In large concessions of 2000-4000 ha for wood chipping in Sabah, a diameter limit of 10.2 cm is

223

used, provided that 100 seed trees per ha are left. Large concessions in Indonesia require felling of trees down to a stem diameter of 7 cm in 50 m wide strips interspaced with 20 m undisturbed strips in a proposed 20-year rotation. Thailand has prescribed the maintainance of a 10 m uncut strip along waterways to reduce the effects of waves and currents on regeneration. Yield A stand of R. apiculata in southern Thailand had an annual leaf production of 7 t/ha and 20 t/ha ofwood. Total aboveground dry matter has been estimated to be 160-190 t/ha in 15-year-old stands in Thailand and 257 t/ha in a 28-year-old stand in Peninsular Malaysia. Genetic resources and breeding It is unlikely that any substantial germplasm collections of R. apiculata are being maintained. There are no known breeding programmes. Prospects Rhizophora forests are being heavily exploited for fuelwood and poles. Recently, they have also been extensively harvested for woodchips or converted for agricultural and aquacultural purposes. Long-term, multiple-use management plans have to be developed and implemented to ensure sustainable use of the remaining resource. R. apiculata, being among the most easily regenerated and widely planted species, will play an important role in those sustainably managed systems. Literature 111Chapman, V.J., 1976. Mangrove vegetation. J. Cramer, Vaduz, Liechtenstein. 447 pp. I2l Hou, D., 1958. Rhizophoraceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana Series I, Vol. 5. Noordhoff-Kolff, Jakarta, Indonesia, pp. 448-457. 131Putz, F.E. & Chan, H.T., 1986. Tree growth, dynamics, and productivity in a mature mangrove forest in Malaysia. Forest Ecology and Management 17: 211-230. I4l Srivastava, P.B.L., Keong, G.B. & Muktar, A., 1987. Role of Acrostichum species in natural regeneration of Rhizophora species in Malaysia. Tropical Ecology 28: 274-288. 151 Srivastava, P.B.L., Majid, N.M. & Shariff, A.H., 1980. Foliage and soil nutrients in Rhizophora apiculata Bl. stands. Tropical Ecology 21: 113-124. 161 Tamai, S. & lampa, P., 1988. Establishment and growth of mangrove seedlings in mangrove forests of southern Thailand. Ecological Research 3: 227-238. I7l Tomlinson, P.B., 1986. The botany of mangroves. Cambridge University Press, Cambridge, United Kingdom. 413 pp. 181 van Vliet, G.J.C.M., 1976. Wood anatomy of Rhizophoraceae. Leiden Botanical Series 3:20-75. D. Hou &H.T. Chan

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AUXILIARY PLANTS

S a m a n e a s a m a n (Jacq.) Merrill J. Wash. Acad. Sei. 6: 47 (1916). L E G U M I N O S A E - MlMOSOIDEAE

In = 26, 14also reported Synonyms Mimosa saman Jacq. (1800-1809), Pithecellobium saman (Jacq.) Benth. (1844), Enterolobium saman (Jacq.) Prain (1897). Vernacular n a m e s Rain tree, monkeypod, cow tamarind (En). Arbre de pluie, saman, zamang (Fr). Indonesia: trembesi, kayudan (Javanese), ki hujan (Sundanese). Malaysia: hujan-hujan, pukul lima (Peninsular Malaysia). Philippines: acacia. Cambodia: 'âmpul barang'. Laos: (do:k) sa:m sa:. Thailand: kampu, chamchuri (central), chamcha (northern). Vietnam: me t[aa]y. Origin and geographic distribution S. saman is a native of northern tropical South America. It is now cultivated and naturalized throughout the tropics, including South-East Asia. U s e s S. saman is commonly grown as a shade tree and as ornamental. It has been planted as a shade tree in cocoa, coffee, vanilla, and in young nutmeg and teak plantations. It can be used as a hedge tree, if lopped heavily. In north-eastern Thailand, mature trees are highly valued as a host for the lac insect (Laccifer lacca). Green leaves of S. saman are a high quality feed for sheep, goats and cattle and are used as a supplement during the dry season. The sweet pods are nutritious and relished by ruminants and pigs, who also take advantage of the shade provided in pastures. Because of its prolific flowering, S. saman is also profitable for honey production. The wood, which is not durable, produces a high quality timber for carving, furniture and panelling. It provides a good quality firewood and charcoal, although it produces much smoke, even when very dry. Where a market for wood carvings exists, it is toovaluable to be used as firewood. Production and international trade The production and trade of S. saman is mainly local and no statistics are available. The famous 'monkeypod' bowls from Hawaii are made of S. saman wood. As the wood is getting scarce, it is now imported in considerable quantities from Indonesia and the Philippines. Properties Per 100 g dry matter the leaves and twigs of S. saman contain 22-27 g crude protein and 44-53 g neutral detergent fibre, the pods and seeds 12-18 g and 38 g respectively. The in vitro digestibility of the leaves is 58-68%, that of the pods is 40%. The mineral content of leaf litter per

100 g dry matter is: N 2.0 g, P 0.3 g, K 0.15 g, Ca 1.16 g, and Mg 0.01 g. Firewood has an energy value of 25 000-27 000 kJ/kg. Dry leaves have the heavy scent of coumarin, reminiscent of newly mown hay. The bark lacks tannins, but yields an inferior gum. The bark and seeds contain a minor, saponin-like alkaloid, pithecolobine. The heartwood ofS. saman is dark walnut to dark chocolate-brown, turning to light brown or goldenbrown with darker streaks when seasoned. The sapwood is whitish. The wood has a basic density at 12% moisture content of 550-700 kg/m 3 and is strong and hard. Shrinkage is extremely low and green wood can be carved out without risk of warping or splitting. It is resistant to dry wood termites. The weight of 1000 seeds is 125-225 g. Description A large, evergreen, unarmed tree, up to 25(-40) m tall at maturity with a trunk diameter at breast height up to 2 m, with widespreading crown up to 25-30 m in diameter. Bark finely fissured, light grey to greyish-brown. Branchlets puberulous to tomentose. Leaves bipinnate, not sensitive to the touch; stipules lanceolate, small, not spinescent, caducous; rachis up to 40 cm long; pinnae 3-9 pairs, up to 11 cm long; concave circular glands present just below the basal pair of pinnae, between all other pairs of pinnae, and at the junction of the leaflets; leaflets opposite, 2-10 pairs per pinna, oblique-ovate to elliptical or subrhomboid, 1.5-6 cm x 0.7-4 cm, apex obtuse-rounded, often emarginate, mucronate, base asymmetrical, upper surface glabrous, lower surface densely short pubescent, main vein diagonal, lateral veins forming a prominent, dense reticulate pattern. Inflorescence a corymb, 2-5 together in the axils of distal leaves; peduncle erect, 5-10 cm long, densely, shortly, yellowish pubescent; corymb with dimorphic flowers, consisting of a larger, 7-8-merous central flower, surrounded by smaller 5-merous marginal flowers; central flower up to 2.5 cm long, sessile, calyx broadly cylindrical, 8-9 mm x 4-5 mm, corolla up to 12 mm long, staminal tube longer than the corolla; marginal flowers up to 3.5 cm long, on short (3 mm) pedicels, calyx funnel-shaped, 5-7 mm long, tomentose or woolly, teeth broadly triangular, acute, 0.5-1 mm long, corolla funnel-shaped, about 10-12 mm long, distal part tomentose or woolly, red or yellowish-red, lobes triangularovate, about 2 mm long, stamens 20-35 mm long, white at the base, purple toward the top, tube shorter than corolla tube. Pod oblongoid, straight

SAMÂNEA

Samanea saman (Jacq.) Merrill - 1, habit; 2,leaf; 3, inflorescence; 4, marginal flower; 5, pod. or slightly curved, 15-20 cm x 1.5-2.3 cm, turgid with thickened margins, indéhiscent, woody, black, about 15-seeded; crustaceous exocarp loosens from the pulpy, sweet mesocarp; endocarp woody, forming one-seeded chambers. Seed ellipsoid, strongly biconvex, 9 mm x 5 mm x 4 mm, brown with a distinct U-shaped pleurogram, shiny, not arillate, aréole elliptical, 7 mm x 3 mm. Seedling with epigeal germination. Growth and development S. saman grows slowly in the first year of planting, but is generally considered to be fast growing. The first two leaves are opposite or sub-opposite, subsequent leaves are arranged spirally. In Thailand, trees reached a height of 1.3 m, 11 months after planting, whereas in Indonesia the height increment was 0.7 m and the diameter increment 1.5 cm in the first 6 months after planting. On average planted stumps reached a height of 2 m, 7.5 months after planting. In a trial plantation in Papua New Guinea, S. saman planted at 2 m x 3 m distance attained an average height of 2.3 m and a diameter of4.5 cm, 8 months after planting.

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Young trees often shed their leaves during the dry season. In Thailand, mature trees flower twice a year, in February-May and in September-November. In Java, flowering is observed from August to April. Fruits mature 5.5-8 months after flowering. S. saman forms N-fixing nodules with strains of Bradyrhizobium. In the Philippines, S. saman proved highly responsive to inoculation with vesicular-arbuscular mycorrhizae and the increase in biomass was 40%compared with uninoculated plants. The abundance of epiphytic ferns and orchids on avenue rain trees, as observed in Peninsular Malaysia, is a striking phenomenon. The trees tend to have a large crown with wide-spreading branches and their branches can stretch right across roads. This habit, however, makes the tree unsuitable for smallholder woodlots. Other botanical information The genus Samanea Merrill is closely related toAlbizia Durazz. and distinction between the two genera is difficult. Some differences are: Samanea: central flower with 7-8 perianth segments (Albizia 5), fruits fleshy and internally segmented (Albizia fruits are not fleshy and usually not segmented inside). A thorough revision of the 2 genera might reveal that they should be united. At night and during cloudy days the leaves of S. saman droop. The extrafloral nectaries excrete sugar-rich juice which sometimes drops from the tree like rain (hence rain tree). At flowering time abundant stamens drop like a shower from the tree canopy from time to time. Ecology S. saman thrives in a wide range of climatic and soil conditions, from sea level up to 1000 m altitude. It is found in both monsoon and equatorial climates with an annual rainfall of 1000-2500 mm. It is not well adapted to climates with a pronounced dry season and withstands only 2-4 dry months. A lower rainfall (700 mm) is tolerated if evenly distributed throughout the year, as in Curaçao. It grows best in climates with a mean minimum temperature of the coldest month of 18-22°C and a mean maximum temperature of the hottest month of 24-30°C. S. saman is rarely found in forest stands and requires high light intensities. Soil requirements range from moderately acidic to alkaline, pH 5.5-8.5. It grows well on clayey or sandy soils and withstands seasonal waterlogging. Propagation and planting S. saman is commonly propagated by seed, but can also be propa-

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AUXILIARY PLANTS

gated through stem and root cuttings. Pods can be collected from the ground. If left in a dark place, the valves are eaten by termites, while the clean seeds are left intact. Mature seed has a hard seedcoat and must be treated for even germination. To break dormancy the seed is immersed in hot water for 3 minutes and then soaked overnight in cool water. Passage through the intestines of herbivores also enhances germination. Germination of untreated seed increases in the course of the first year of storage. Seed sown in containers placed in full light generally have a germination rate of over 90%. Seedlings can be planted in the field after 6-8 weeks when they are 15-25 cm tall. They may be stumped with a root length of 40 cm, a shoot length of20 cm, and a diameter of0.5-3 cm. When grown for fodder, seedlings are spaced at 3 m x 1 m. Spacings of 4 m x 4-8 m are recommended for wood production. In the Philippines, S. saman is planted at 10 m x 10 m spacing in coffee plantations grown at 3 m x 3 m. Husbandry S. saman planted on paddy bunds in north-eastern Thailand increased the organic matter content of the topsoil from 0.36% to 0.58% and the total soil nitrogen from 0.06% to 0.08%, while the pH increased from 4.8 to 5.8 under the trees. However, shading also caused a reduction in the yield of rice. In Malaysia, an increase in growth, yield and nutritive quality of the pasture grass Axonopus compressus (Swartz) P. Beauv. was observed when grown under S. saman. This is attributed to the higher N content ofthe soil and a beneficial micro-climate under the trees. Folding of the leaves and drooping branches allow rainfall to reach the grass directly during the night and on cloudy days (another reason for the name rain tree). On sunny days, the unfolded leaves provide shade and help to conserve moisture. When planted in hedges trees should be maintained by heavy lopping. In north-eastern Thailand, S. saman is pollarded at 1m height every six months for the production of fodder. Pollarding is also used for firewood production. For lac production in north-eastern Thailand, lac insects are usually cultured on the trees during December and February. The lac can be harvested 12 months later. After harvesting, the trees are left uncut for at least 3 years before restarting the lac cultivation. Diseases and pests A wound parasite, Ganoderma lucidum is reported from the Philippines. It may cause white soft rot in the lower part of the stem. A powdery mildew (Erysiphe communis) is very common in nurseries and may cause com-

plete defoliation of seedlings. Two psyllid species attack S. saman, but rarely cause serious damage. The leucaena psyllid (Heteropsylla cubana) feeds on young shoots and in severe cases may cause defoliation, stunted shoot growth and eventually the death of the tree. Psylla acacia-baileyanae feeds on the shoots, often causing leaves and shoots to curl. Yield Annual increment of wood is 10-15 nr'Vha when harvested 10-15-years after planting. Yields of lac depend on tree size, but annual amounts of 50-100 kg per tree have been obtained. Genetic resources and breeding Neither substantial germplasm collections nor breeding programmes ofS. saman are known to exist. Prospects S. saman is a valuable multipurpose tree. It is easily raised and can grow under a wide range of environmental conditions. The slow initial growth is a disadvantage for wood or fodder production. The integration of lac production with firewood and timber production warrants further studies. Literature 111 Akkasaeng, R., Gutteridge, R.C. & Wanapat, M., 1989. Evaluation of trees and shrubs for forage and firewood in north-east Thailand. The International Tree Crops Journal 5: 209-220. 12! Gutteridge, R.C, 1990. Agronomic evaluation oftree and shrub species in South-East Queensland. Tropical Grasslands 24: 29-34. 131 Nielsen, I.C., 1992. Mimosaceae (Leguminosae Mimosoideae). In: de Wilde, W.J.J.O., Nooteboom, H.P. & Kalkman, C. (Editors): Flora Malesiana, Series 1, Vol. 11(1). Foundation Flora Malesiana, Leiden University, Leiden, the Netherlands, pp. 155-156. 141 Nitrogen Fixing Tree Association, 1987. The multi-purpose rain tree, Samanea saman. NFTA, Waimanalo, Hawaii, United States. 2 pp. 151 Quiniones, S.S. &Dayan, M.P., 1981.Notes on the diseases offorest species in the Philippines. Sylvatrop 6: 61-67. 161 Relwani, L.L., Lahane, B.N. & Gandhe, A.M., 1988. Performance of nitrogen-fixing MPTS on mountainous wasteland in low rainfall areas. In: Whithington, D., MacDicken, K.G., Sastry, C.B. & Adams, N.R. (Editors): Multipurpose tree species for small farm use. Winrock International Institute for Agriculture Development and International Development Research Center ofCanada, pp. 105-113. 171 Sae-Lee, S., 1990. Effect of trees in rice paddies on soil fertility and rice growth. MSc.-thesis in Soil Science, Graduate School, Khon Kaen University, Khon Kaen, Thailand. 172 pp. [in Thai with English abstract]. 181Zhou, X.Q. & Han, S.F., 1984. Studies on symbiotic system of nodule bacteria and tree

SCHLEICHERA

legumes. 1. Nodulation, isolation, and reciprocal cross inoculation. Journal of Nanjing Institute of Forestry 2: 32-42. R. Akkasaeng

S c h l e i c h e r a o l e o s a (Lour.) O k e n Allg. Naturgesch. Bot.2:1341 (1841). SAPINDACEAE

2« =32 Synonyms Pistacia oleosa Lour. (1790), Schleichera trijuga Willd. (1806), Cussambium oleosum O. Kuntze(1891). Vernacular n a m e s Macassar oil tree, gum-lac tree, Ceylon oak (En). Qennettier-rose, pongro (Fr). Indonesia: kosambi (Javanese), kasambi (Sundanese). Malaysia: kusambi. Cambodia: pongro. Laos: (do:k) phen (Spire). Thailand: machok (northern), takhro (north-eastern). Vietnam: c[oj] ph[ef]n, c[aa]y vanrao, pongro. Origin and geographic distribution S. oleosa occurs naturally from the foothills of the Himalayas andthewestern Deccan toSriLanka and Indo-China. Itwasprobably introduced to Malesia and has naturalized in Indonesia (Java, the Lesser Sunda Islands (Bali and Nusa Tenggara), Sulawesi, the Moluccas, Ceram andtheKaiIslands). It is occasionally cultivated throughout the tropics, especially in India. U s e s S. oleosa has many important uses. The wood is suitable as firewood and makes excellent charcoal; the pinkish-brown heartwood is very hard and durable, excellent to make pestles, cartwheels, axles, ploughs, tool handles, androllersof sugar mills and oilpresses. Oilextracted from the seed, called 'kusum oil',isa valuable component of true Macassar oil used in hairdressing; it is also used for culinary andlighting purposes andin traditional medicine itis applied tocure itching, acne and other skin afflictions. Unguents are made of the harder fraction ofthe oil.In Madura and Java the oilis used in the batik industry, andin southern India as a cooling bath oil. Thepleasantly acid arillodes ofthe ripe seeds are eaten, whereas immature fruit ispickled. Cooked young leaves make a side dish. Powdered seeds are applied to wounds and ulcers of cattle to remove maggots. A dye is obtained from the bark. Thebark contains tannin and isastringent andused against skin inflammations and ulcers, while an infusion is taken against malaria. It used tobeutilised occasionally for tanning leather. Leaves, twigs and seed-cake are used to feed cattle. In India S. oleosa is used

227

as host for the lac insect (Laccifer lacca). The product is called kusum lac and is the best in quality and in yield. In Central India, S. oleosa is much planted asa wayside tree. Properties The energy value of the wood is about 20800 kJ/kg. The oil content of the kernel varies from 59-72%. The oil is yellowish-brown and semi-solid and consists of oleic acid (52%), arachidic acid (20%), stearic acid (10%), gadoleic acid (9%). It also contains cyanogenic compounds, which may cause giddiness and should be removed if the oil is used for human consumption. The press cake contains per 100g approximately: water 5.5 g, protein 22 g, fat 49 g, carbohydrates 14g,fibre 5g,ash3.5g. The leaves contain per 100g dry matter approximately: crude protein 10.5g, ether extract 2g,Nfree extract 49g, crude fibre 32.5g.Thebark contains about 10% tannin and the analgesic compound lupeol and the antitumour agents betulin and betulic acid have been isolated from it. The heartwood ofS. oleosa is pinkish-brown, very hard and durable, but cracks very easily during seasoning. Toavoid cracking, logs should be sawn when green and the sawn timber closely stacked; the piles should be protected from the sun and from drying wind. Thewood canbekiln-dried satisfactorily. The wood is very durable under cover, but not durable when exposed. It takes preservatives well. Drywood is very hard to saw,it canbe planed to a very smooth surface which takes a high, lasting polish. The weight of 1000 seeds is 500-700 g. Description Dioecious, deciduous tree, up to 40 m tall. Bole occasionally upto2m in diameter, but generally much less, usually crooked and slightly buttressed. Bark smooth, grey. Branches terete, striate, with sparse, short fulvous sericeous hairs when young and with sessile glands, black, later yellowish-brown to ashy. Leaves paripinnate, (2-)3(-4)-jugate, the topmost leaflet sometimes situated like a terminal leaflet; axial parts usually early glabrescent; petiole terete to somewhat flattened or slightly grooved above, 2-6(-8) cm long, pulvinate; rachis terete to triangular; petiolule swollen, slightly grooved above, 1-3 mm long; leaflets elliptical to obovate, 4 . 5 18.5(-25) cm x 2.5-9 cm, chartaceous to coriaceous, dark brown or greyish-green above, lighter brown to greenish beneath, deep purple when young, base subacute to cuneate, often oblique, margin entire to repandous, apex obtuse or emarginate, sometimes shortly acuminate, veins in 12-15 pairs, looped and joined near the margin.

228

AUXILIARY PLANTS

Schleichera oleosa (Lour.) Oken - 1, habit; 2, fruiting branch; 3, male flower; 4, female flower; 5, spiny fruit. Inflorescence 6-15 cm long, situated in the defoliated part of branchlets above leaf scars, sometimes axillary, consisting of a few simple (female) or sparsely branched (male) thyrses, the basal part with scattered, many-flowered fascicles, the upper part spicate, sparsely hairy; flowers functionally unisexual, pale yellow or pale green; pedicel up to 5 mm long; sepals 4-5, connate at base, lobes ovate to deltoid, about 1.5 mm long, obtuse to acute, with thin hairs on both sides, margin ciliate and sometimes glandular, deciduous in fruit; disk uninterrupted, patelliform, sinuate; petals absent; stamens 5-9, filaments about 2 mm long, sparsely hairy, much reduced in female flowers; ovary ovoid, slightly 3-angular and indistinctly 3-sulcate, about 1.3 mm long, style rather thick, up to 1.5 mm long, pistil much reduced in male flowers. Fruit a broadly ovoid, ellipsoid to subglobular berry, 1-2-seeded, 1.5-2.5 cm x 1-2 cm, base narrowed, apex pointed, yellow, hardcrustaceous, smooth or slightly spiny. Seed subglobular, about 12 mm x 10 mm x 8 mm, hilum orbicular, testa brown, smooth, glabrous; arillode

completely covering the seed, thin papery, yellow. Growth and development S. oleosa is deciduous, but completely leafless for a few days only. In India, leaves drop in December. It flowers at the beginning of the dry season and fruits about 6 months later. S. oleosa produces root suckers freely and pollards well. In cultivation, it does not stand heavy pruning, since growth is rather slow. In Bihar (India), trees grow to a height of about 7 m and a stem diameter of 10 cm in 16years; in Uttar Pradesh (India) coppice shoots reach a height of 2 m in 1year, in South Kanara (India) 5 m in 3 years. Ecology S. oleosa requires 750-2500 mm annual rainfall and a dry season, which explains its absence from western Malesia. It tolerates absolute maximum temperatures of 35-47.5°C and absolute minimum temperatures of-2.5°C. In Java, it occurs usually at low altitudes, but can be found up to 900(-1200) m. It occurs spontaneously in dry, mixed deciduous forest and savanna with only scattered trees, sometimes gregariously. In Java, it is found in areas with natural teak forest. It grows on rather dry to occasionally swampy locations on various, often rocky, gravelly or loamy, well drained, preferably slightly acid soils. S. oleosa is fire-resistant. Seedlings are frost sensitive and light-demanding. Propagation and planting Natural regeneration is by seed and root suckers. Seed can be stored in gunny bags for 1year, in sealed containers for up to 2 years. Propagation is by direct sowing in thoroughly prepared soil or by stump planting. In nurseries in West Bengal (India), seed is sown 7.5 cm apart immediately after collection. Stumps are prepared after one year, when the seedling stem is about 1cm in diameter. The stem is cut back to about 4 cm, the roots to 25 cm. Plant holes should be about 30 cm deep and wide. Regular weeding and protection from grazing is required. Husbandry When S. oleosa is employed as a host for lac insects in northern India, trees are inoculated early in the rainy season (June-July) or in January-February. Shoots of 4-10 months old are most suitable for larval settlement. Lac is harvested after about 6 months. Only trees with a fully developed crown produce a good yield of lac. Trees can be improved by heavy pollarding. Trees should be rested for 12-18 months before being reinoculated. Diseases and pests Stem blight (Rosellinia bunodes), yellow cork rot (Polyporus weberianus), white spongy rot (Daedalea flavida and Hexago-

SENNA

nia apiaria) and white fibrous rot (Irpex flavus) are important diseases in India. Several defoliators, borers and sap suckers cause damage. The seed is attacked by a bug (Serinetha augur). Yield In India, a mature tree yields 21-28 kg depulped seed per year. Handling after harvest For depulping, fruits are kept in heaps for 2-4 days and are then rubbed clean. After crushing the depulped seed, the oil is extracted by boiling or pressing. The oil yield obtained by boiling is 32-35% of the kernel weight, by pressing 25-27%. Raw lac is harvested with the branches as sticklac. It is washed, dried and winnowed to yield a granular substance called seed-lac. Prospects Where wild S. oleosa occurs abundantly, it remains important as a fuelwood, but its growth is too slow to be planted for fuel. Where seed is available in large amounts, pressing and refining of oil combined with the manufacturing of seed cake as cattle feed may be viable, although the quantity currently processed is well below its potential. As a host of the lac insect, S. oleosa is preferable to other hosts. Depending on demand for natural lac, it may be useful in village industry. Literature 111 Axtell, B.L. & Fairman, R.M., 1992. Minor oil crops. Food and Agricultural Organization of the United Nations (FAO) Agricultural Services Bulletin, No 94. pp. 83-85. 121 Council of Scientific and Industrial Research (CSIR), 1972. The wealth of India. Raw Materials. Vol. 9. Publications & Information Directorate, CSIR, New Delhi, India, pp. 250-254. 131 Iwasa, S., 1974. Useful crops of the tropics. Tropical Agriculture Research Center, Ministry of Agriculture and Forestry, Japan, pp. 383-386. 141 Jain, R.K., 1994. Fuelwood characteristics of medium tree and shrub species of India. Bioresource Technology 47: 81-84. 151 Leenhouts, P.W., 1994. Sapindaceae. Schleichera. In: Flora Malesiana, Series 1,Vol. 11. Foundation Flora Malesiana, Rijksherbarium, Leiden University, Leiden, the Netherlands, pp. 727-729. 161 Radijanto, S.B., 1979. Model untuk penaksiran lak pada tanaman inang Schleichera oleosa Merr. [A model for estimating the lac production of Schleichera oleosa Merr. as a host plant]. Duta Rimba (Indonesia) 5 (31): 13-23. 171 Rappard, F.W., 1951. The organization of the lac cultivation in Indonesia. Indonesian Journal of Natural Sciences 107: 104-106. S. Iwasa

229

Senna didymobotrya (Fresenius) Irwin & Barneby Mem. New York Bot. Garden 35:467 (1982). LEGUMINOSAE - CAESALPINIOIDEAE

2n = 28 Synonyms Cassia didymobotrya Fresenius (1839), C. verdickii de Wildeman (1900), C. nairob(i)ensis L.H. Bailey (1941). Vernacular n a m e s Candelabra tree, wild senna (En).African wild sensitive plant (Am). Origin and geographic distribution S. didymobotrya is a native of tropical East and Central Africa, from Ethiopia and Sudan to Angola and Mozambique. It was introduced into tropical Asia and America as a green manure and cover crop, and later as an ornamental. It sporadically naturalized in frostless regions, including Malesia. It is now grown throughout the world as an ornamental. Uses S. didymobotrya was introduced as a cover crop and green manure in India, Sri Lanka, Peninsular Malaysia and Java and has been used as a shade tree in tea plantations. In sites where Erythrina spp. do not grow well, S. didymobotrya may be a valuable substitute. It is now also popular as an ornamental plant owing to its bright yellowflowers and black-green bracts. In Africa, S. didymobotrya is commonly used as a stupefacient poison for fishing and as ornamental plant. Medicinally, it is widely used as a purgative and an anti-malaria medicine. A decoction of the leaves is used against stomach complaints. Properties The aboveground biomass of S. didymobotrya grown as ground cover in Sri Lanka was found to contain 0.7 g N per 100 g fresh material. Leaves and roots contain a number of anthraquinones, choline, and the trisaccharide raffinose. In vitro cultures of S. didymobotrya produced chemical compounds that can be converted into low-energy sweeteners and insecticides. When in flower or-bruised, the plant emits an unpleasant smell said to be very reminiscent ofmice. Botany Usually a several-stemmed shrub or small tree, 0.5-5(-9) m tall. Branches terete, striate, pubescent to villous, rarely subglabrous. Leaves simply paripinnate, narrowly oblong-elliptical in outline, 10-50 cm long; stipules broadly ovate-cordate, 6-17 mm x 8-10 mm, acuminate, palmately veined, reflexed, tardily caducous; petiole terete, 1-8 cm long, rachis up to 40 cm long, both pubescent and eglandular; petiolules up to 3 mm long; leaflets in 8-18 pairs, chartaceous, elliptical-oblong, 2-6.5 cm x 0.5-2.5 cm, 2-3 times

230

AUXILIARY PLANTS

cent; style slender, glabrous, recurved, about 1cm long; stigma punctiform. Fruit a flat, 9-16-seeded pod, linear-oblong, 7-12 cm x 1.5-2.5 cm, glabrescent, short beaked, dehiscent or indéhiscent when dry, depressed between the seeds, sutures raised, blackish-brown. Seed flattened, oblongoid, apiculate, 8-9 mm x 4-5 mm x 2.5 mm, smooth, pale brown; aréole elliptical, 3-4 mm x 0.7-1.5 mm. Juvenile stems tend to be somewhat tender and should be staked. When growth is very rapid, plants are apt to become straggly. S. didymobotrya withstands lopping well. It flowers profusely twice a year; in temperate regions it flowers throughout the summer. The bracts, stipules and indumentum of S. didymobotrya are quite variable. In the axil of the leaves an abortive inflorescence is often present.

Senna didymobotrya (Fresenius) Irwin & Barneby - 1, flowering and fruiting branch; 2, stipule; 3, side view of flower; 4, longitudinal section through flower; 5, seed. longer than wide, base oblique, apex rounded but mucronate, pubescent to glabrescent, marginal veins distinct. Inflorescence an erect, axillary, 20-30-flowered, spike-like raceme, 10-50 cm long; peduncle terete, 5-8 cm long, pubescent; bracts broadly ovate, 8-27 mm x 5-15 mm, black-green, at first imbricate and enclosing the flower buds; bracteoles absent; pedicel slender, 3-10 mm long, densely pubescent; sepals 5, subequal, oblong-obovate, 9-14 mm long, puberulous, green; petals 5, slightly unequal, at first incurved, later on more spreading, ovate to obovate, 17-27 mm x 10-16 mm, with a slender, about 1 mm long claw, glabrous, bright yellow, delicately veined; stamens 10, filaments shorter than anthers, anthers of 2 lower stamens 9-11 mm long, 3 upper stamens staminodial, anthers of 5 median stamens about 5 mm long; ovary and stipe velvety pubes-

In the older literature, this species is best known as Cassia didymobotrya. Until the beginning of the 1980s, Cassia L. was considered to be a genus with over 500 species. The large genus Cassia L. emend. Gaertner has now been subdivided into 3 genera: Cassia (trees, some filaments curved, bracteoles present, no aréoles on seed), Senna Miller (herbs, shrubs or trees, all filaments straight, bracteoles absent, aréoles on seed) and Chamaecrista Moench (herbs or shrubs, all filaments straight, bracteoles present, no aréoles on seed). Cassia now has about 30 species, Senna and Chamaecrista comprise about equal numbers of species. Ecology In its natural habitat S. didymobotrya is often ruderal in riparian montane wooded grassland or evergreen bushland, at 900-2400 m altitude. It tolerates light frost. Agronomy S. didymobotrya is easily propagated by seed; cuttings are said not to be successful. The seed may be sown in the nursery or directly in the field. When planted as a small shade tree in tea it is spaced at about 5m x 5 m. The plants can be lopped several times per year to provide green manure. Lopping is preferably done when the plants are in flower, when the nutrient content in the leaves is high. The plant yields a fairly large amount ofloppings. About 5 t of green material provides 35.5 kg nitrogen. In temperate areas, potted ornamental plants are overwintered in greenhouses. S. didymobotrya is hardy and quite free from diseases and pests. Prospects S. didymobotrya used to be a ground cover and green manure crop, appreciated mainly as an alternative plant in locations where Erythrina spp. did not flourish. It has now been largely replaced as a green manure crop by species such

SENNA

as Tephrosia Candida (Roxb.) D C , T. purpurea (L.) Pers. and T. vogelii Hooker f. Its potential as an ornamental pot plant is being developed. Literature 111 Botta, B. & delle Monache, G., 1993. Cassia didymobotrya (wild senna): in vitro culture, biotransformation and the production of secondary metabolites. In: Bajaj, Y.P.S. (Editor): Biotechnology in agriculture and forestry. Vol.21, 4. Medicinal and aromatic plants. Springer, Berlin, Germany, pp. 64-86. 121 de Wit, H.C.D., 1955. A revision of the genus Cassia in Malaysia. Webbia 11:241-242. 131Holland, T.H., 1931. Alternative green manure plants. Tropical Agriculturist 76: 135-136. 141 Irwin, H.S. & Barneby, R.C., 1982. The American Cassiinae. A synoptical revision of Leguminosae tribe Cassieae subtribe Cassiinae in the New World. Memoirs of the New York Botanical Garden 35(2): 467-468. I5l Steyaert, R., 1952. Cassieae. Flore du Congo beige et du Ruanda-Urundi. Vol. 3. Institut National pour l'Etude Agronomique du Congo Belge (INÉAC), Brussels, Belgium, pp. 504-506. 161Wilkinson, C.H., 1937. Ground cover on tea estates in Dimbula. Tea Quarterly 10: 206-209.

smell can be reduced by relatively long cooking. In Java the leaves are used medicinally for treating herpes. A decoction of the leaves is used against irritations of the skin in Thailand. In Laos the seeds are used as a substitute for coffee. Production and international trade S. hirsuta is very occasionally sold in village markets, but there are no production data. Properties The seed contains a water-soluble gum, though not in commercial quantities; it also contains a bi-anthraquinone and a tri-terpenoid, which may prove medicinally important. The weight of 1000 seeds is 4 g. Botany Erect or diffuse, simple or severalstemmed herb, up to 2.5 m tall, becoming softwoody with age, with a fetid smell, hairy but highly diverse in pubescence; twigs grooved and ribbed, densely hairy. Leaves simply paripinnate, 10-20 cm long; stipules linear-acute, 3-15 mm long, usually not persisting; petiole stout, up to 6.5 cm long, villose, above the insertion with a sessile, oblong gland; rachis 3-16 cm long, glandless;

B. Sunarno

S e n n a h i r s u t a (L.) I r w i n & B a r n e b y Phytologia 44 (7):499 (1979). LEGUMINOSAE - CAESALPINIOIDEAE

2n = 28, 56; 2« = 16 + IB is reported from Nigeria Synonyms Cassia hirsuta L. (1753), C. leptocarpa Benth. (1849). Vernacular n a m e s Woolly wild sensitive plant (En). Indonesia: kasingsat bulu (general), kasingsat (Sundanese). Malaysia: sinteng, kacang kayu. Philippines: balbala tungan, katanda, tighiman (Tagalog). Thailand: phong pheng (northern), dapphit (peninsular). Vietnam: mu[oof]ng r[uwf]ng. Origin and geographic distribution S. hirsuta is a native oftropical America and is now distributed throughout Malesia, Indo-China, Thailand and most other countries in the Asian and African tropics. In Java, where it has long been known and has naturalized, it is more common in West Java than towards the east. U s e s S. hirsuta is used as a green manure and forage plant. In Africa it is planted as a shade plant in young coffee plantations. The leaves and young pods are eaten, usually steamed or cooked in vegetable dishes or in salads. The unpleasant

231

Senna hirsuta (L.) Irwin & Barneby - 1, flowering and fruiting branch; 2, leaflet; 3,part of branch; 4, flower with sepals and petals removed; 5, pod.

232

AUXILIARY PLANTS

petiolules up to 3.5 mm long, slender, villose, often not quite opposite; leaflets 2-8 pairs, strongly accrescent distally, chartaceous, lanceolate-acuminate, 2-12.5 cm x 1-5 cm, 2-6 times as long as wide, slightly unequal-sided, base acute or rounded, dark green, roughly villose on both surfaces. Inflorescence an axillary or rarely terminal, 2-8flowered raceme (up to 45 in South America), l(-8) cm long, aggregate in leafy panicles; peduncle up to 3 cm long; bracts linear to lanceolate, 1.5-5 mm long, early caducous; bracteoles absent; pedicel 1-2.5 cm long, pubescent; sepals 5, unequal, 2 outer ones small, orbicular, 4-7 mm long, hairy, 3 inner ones larger, 7-10 mm long, partly glabrous; petals 5, unequal, obovate, 8-28 m long, yellow, glabrous, short-clawed; stamens 10, 2 large with flat filaments 4-7 mm long and curved anthers 7-8 mm long opening by apical pores, 4 smaller and 4 staminodial; ovary woolly, recurved; style short, glabrous with hairy subapical stigma. Fruit a falcate to straight angular pod, 6-28 cm x 3-7 mm, septate, 50-90-seeded, strigose. Seed slightly compressed, orbicular, about 3 mm in diameter, dark olive coloured; aréole narrowly elliptical, 0.5-2.5 mm long. S. hirsuta is very variable and 7 varieties have been distinguished for South America. In SouthEast Asia, 2 varieties occur: var. hirsuta (widespread as a weed in South-East Asia and the rest ofthe Old World tropics; fruit straight, 11-15 cm x 4-6.5 mm, bristly-hirsute) and var. puberuia Irwin &Barneby (widespread in South America, but in South-East Asia only present in the Philippines as a weed, fruit simply arched outward, 15-25 cm x 3-6 mm). In South-East Asia S. hirsuta flowers throughout the year. The usually numerous fruits are curved when young and straight when mature; they are characterized by somewhat raised, glabrescent sutures and woolly strigose sides. The synonymous name Cassia hirsuta is still commonly used in the literature. Until the beginning of the 1980s, Cassia L. was considered to be a genus with over 500 species. The large genus Cassia L. emend. Gaertner has now been subdivided into 3 genera: Cassia (trees, some filaments curved, bracteoles present, no aréoles on seed), Senna Miller (herbs, shrubs or trees, all filaments straight, bracteoles absent, aréoles on seed) and Chamaecrista Moench (herbs or shrubs, all filaments straight, bracteoles present, no aréoles on seed). Cassia now has about 30 species, Senna and Chamaecrista comprise about equal numbers of species. Ecology In South-East Asia S. hirsuta is found

in plains and hilly areas up to about 700 m altitude. It grows spontaneously in waste locations, along roadsides, railway embankments, dry ditches and in secondary forest. It is found in gardens and fields as a weed and prefers open locations. Agronomy S. hirsuta is propagated by seed. As a green manure S. hirsuta is fast growing, easy to cut, coppices well and can produce considerable amounts of foliage material in a growth cycle of 8 months. Observations in Central Africa indicate that it competes poorly with weeds. It is very susceptible to Corticium salmonicolor and is also affected by a root disease (Rosellina sp.), and by Sclerotium rolfsii. Prospects S. hirsuta is one ofthe Senna species which has been proposed as a green manure crop. However, research has so far not confirmed its potential for green manure, pasture, or forage. Literature 111 Gill, L.S. & Husaini, S.W.H., 1985. Caryological evolution of the southern Nigerian Leguminosae. Revue de Cytologie et de Biologie Végétales. Le Botaniste 8:3-31. I2l Groth, D., Boaretto, M.R. &da Silva, R.N., 1983. Morfologia de sementes, frutos e plantas invasores em algunas culturas [Seed, fruit and plant morphology in weeds of several crops]. Revista Brasileira de Sementes 5: 151-182. 131Irwin, H.S. & Barneby, R.C., 1982. The American Cassiinae. A synoptical revision of Leguminosae tribe Cassieae subtribe Cassiinae in the New World. Memoirs of the New York Botanical Garden 35:425-435. I4l Larsen, K. & Larsen, S.S., 1984. Cassia. In: Smitinand, T. & Larsen, K. (Editors): Flora of Thailand. Vol. 4(1). Leguminosae-Caesalpinioideae. The Forest Herbarium, Royal Forest Department, Bangkok, Thailand, p. 113. 151Ochse, J.J. & Bakhuizen van den Brink, R.C., 1980. Vegetables of the Dutch East Indies. 3rd English edition (translation of 'Indische Groenten', 1931). Asher, Amsterdam, the Netherlands, pp. 375-376. 161Verdcourt, B., 1979. A manual of New Guinea legumes. Botany Bulletin No 11. Office of Forests, Division of Botany, Lae, Papua New Guinea, pp.45,47. H. Sangat-Roemantyo

Senna siamea (Lamk) Irwin & Barneby Mem. New York Bot. Garden 35:98 (1982). LEGUMINOSAE - CAESALPINIOIDEAE

2n = 28 Synonyms Cassia siamea Lamk (1785), C. florida Vahl (1794), Senna sumatrana (Roxb. ex Hörnern.) Roxb. (1832).

SENNA

Vernacular names Siamese senna, kassod tree, Thailand shower (En). Indonesia: johar (general), bujuk, dulang (Sumatra). Malaysia: johor, sebusok, guah hitam. Philippines: robles. Cambodia: 'ângkanh'. Laos: 'khi:z hlek. Thailand: khilek (general), khilek-luang (northern), khilek-yai (central). Vietnam: c[aajy muLoofJng den, muLoofJng xi[ee]m, humbo (Thuân Hai). Origin and geographic distribution S. siamea is native to South and South-East Asia, from Thailand and Burma (Myanmar) to southern India and Sri Lanka. However, it has been cultivated for so long, that its exact origin is unknown. It is widely planted throughout the tropics and is locally naturalized. U s e s S. siamea is grown as a shade tree along roads and in coffee and tea plantations and is often planted as an ornamental. There is increasing interest in its use as a source of mulch, especially in alley-cropping systems. In drier regions such as northern India it is planted as a wind-break and shelter-belt, while in other tropical regions it is used extensively for rehabilitation of degraded lands. It is also used to revegetate aluminium mine tailings (red mud). In Thailand and Indo-China, young fruits and leaves are eaten as a vegetable. During preparation, the cooking liquid is replaced three times to remove toxins. The flowers and young leaves are used in curries in Sri Lanka. S. siamea is not widely grown for fodder, but the trees are browsed and plantations should be protected from livestock and wildlife. In Bangladesh, browsing by deer caused a 70% reduction in growth in the first year in unfenced plots. The alkaloids and other secondary plant compounds in the leaves, flowers and pods ofS. siamea are highly toxic to non-ruminants, like pigs and poultry, and these animals should be excluded from plantations. Caution should be exercised when feeding the leaves to ruminants, since little is known about the long-term effects. S. siamea is used as a host plant for the lac insect in China, while in India it is used as a host for sandalwood (Santalum sp.), a parasitic tree producing the well-known aromatic wood. The oil from the seeds is a minor source of vernolic and cyclopropenoid fatty acids. The dark heartwood is used for joinery, inlaying, handles, sticks and other decorative uses. The wood has also been used for posts, poles, bridges, mine poles, beams and produces excellent firewood and charcoal. Large plantations ofS. siamea were established in Ghana, Nigeria and Sierra Leone in the 1920s

233

mainly for this purpose. All parts of the plant can be used for tanning. In traditional medicine, the root is used to charm away intestinal worms and to prevent convulsions in children. The heartwood is said to be laxative and in Cambodia a decoction is used against scabies. Properties Leaves ofS. siamea contain per 100 g dry matter approximately: N 1.7-3.0 g, P 0.1-0.2 g, K 0.5-1.2(-1.9) g, Ca 1.6-2.8 g, Mg 0.2-0.25 g, Na 0.02 g, S 0.2 g, polyphenols 1.5 g, cellulose 18 g, lignin 6.6 g, and hemicellulose 22 g.Annual leaf fall of S. siamea as high as 6.1 t/ha has been reported, providing per ha: 113 kg N, 40 kg K, 91 kg Ca, and 13 kg Mg. Per 100 g dry matter, neutral detergent fibre and acid detergent fibre contents were 42 g and 40 g, respectively, the ash content was 5.2 g, lignin 23 g. In vitro dry matter digestibility has been measured at 62-65%,which is consistent with the relatively low fibre content. The leaves and other plant parts produce many chemicals: anthraquinones, anthrones, flavones, triterpenoids and alkaloids, including cassiadimine, a chromone alkaloid. Tannin is present in the bark (9%), leaves (17%) and fruits (7%). The dense, dark coloured wood of S. siamea makes good fuel, although it does produce some smoke when burning. The energy value of the wood is 22 400 kJ/kg, the density is 600-800 kg/m3. The wood sometimes produces a yellow powder that may cause irritation to the skin. The weight of 1000 seeds is 25-28 g. Description Tree, 6-12(-30) m tall, with spreading branches forming a dense rounded crown. Bark almost smooth, grey, young shoots ribbed. Leaves simply paripinnate, oblong-elliptical in outline, 10-35 cm long; stipules subulate, 1 mm long, very early caducous; petiole terete but with a shallow ventral groove, 1.5-3.5 cm long, glandless; rachis 4.5-25 cm long, glandless; petiolule 2-4 mm long; leaflets in 4-16 pairs, subcoriaceous, oblong to ovate-oblong, 3-8 cm x 1-2.5 cm, 2-4 times as long as wide, base unequal-sided rounded to cuneate, apex rounded to refuse or blunt, often mucronate, glossy and glabrous above, dull and rough to delicately puberulous below. Inflorescence an erect, terminal, 10-60-flowered, leafy panicle, 15-60 cm long, composed of numerous dense corymbs up to 10 cm x 5-6 cm; peduncle robust, 5-7 cm long; bracts obovate in lower half, suddenly narrowing into a linear acute top 3-6 mm long, puberulous, early caducous; bracteoles absent; pedicel 2-3.5 cm long; sepals 5, unequal, rounded-ovate, 4-9 mm long, thick, pu-

234

AUXILIARY PLANTS

Senna siamea (Lamk) Irwin & Barneby - 1, habit tree; 2, flowering and fruiting branch; 3, flower; 4, pods. berulous, repanding-reflexed, long persistent; petals 5, orbicular-obovate, 1-2 cm long, yellow, glabrous, standard with 1-2 mm long claw; stamens 10, 3 lower ones with 6 mm long filaments and 5 mm long anthers, 3 upper ones staminodial, 4 meridian ones with 3-4 mm long filaments and 5 mm long anthers; ovary shortly tomentellous, style 4-5 mm long, stigma punctiform. Pod flattened, 20-30-seeded, 15-30 cm x 12-16 mm, alternately bulging and depressed in the centre, rim thick, glabrescent, dull, finally dehiscent. Seed very flat ovoid, 6.5-8 mm x 6 mm, light brown, glossy; aréole oblong-elliptical, 3-4.5 mm x 1 mm. Growth and development Mature seed germinates readily after scarification. The first leaves are 1-jugate. Early seedling growth can be quite slow in comparison to Gliricidia sepium (Jacq.) Kunth ex Walp. and Leucaena leucocephala (Lamk) de Wit, growing to only 29 cm in 8 weeks after planting. After this early phase, growth may be quite rapid. Trees show Scarrone's

architectural model, with an indeterminate trunk bearing tiers of orthotropic branches, which branch sympodially as a result of terminal flowering. Once established, flowering is precocious and abundant throughout the year. It starts flowering and fruiting at the age of 2-3 years. Fruits remain long on the tree. Unless carefully pruned, it ages ungracefully, the crown becoming straggling and misshapen with upright and drooping branches. In many species comparison trials, S. siamea has ranked in the top 2 or 3 with respect to biomass production in the first 2-3 years. In a test of 17 multipurpose tree species in southern Sumatra, S. siamea gave the highest leaf yield of up to 1200 g per plant per year. It also performed better than 16 other species tested in experiments in the highlands of Uganda, reaching a height of 8 m and a root collar diameter of20 cm in 40 months. The root system consists of a few thick roots, growing to considerable depth and a dense mat of rootlets in the top 10-20 cm of the soil, which may reach a distance of 7 m from the stem in 1 year and eventually a distance ofup to 15 m. As with many species of the subfamily Caesalpinioideae, S. siamea does not nodulate and does not fix nitrogen through Rhizobium symbiosis, although there is some evidence that nitrogen-fixing activity may occur in the warty, lenticellate bark. S. siamea forms ecto-mycorrhizae. Other botanical information In older literature, this species is best known as Cassia siamea. Until the beginning of the 1980s, Cassia L. was considered to be a genus with over 500 species. The large genus Cassia L. emend. Gaertner has now been subdivided into 3 genera: Cassia (trees, some filaments curved, bracteoles present, no aréoles on seed), Senna Miller (herbs, shrubs or trees, all filaments straight, bracteoles absent, aréoles on seed) and Chamaecrista Moench (herbs or shrubs, all filaments straight, bracteoles present, no aréoles on seed). Cassia now has about 30 species, Senna and Chamaecrista comprise about equal numbers of species. A chemotaxonomic study of 28 Indian species ofSenna and Cassia revealed that the terpenoid lupeol (considered a primitive character), was present only in S. siamea, suggesting that it may be the ancestor of the modern sennas and cassias. Ecology S. siamea will grow in a range of climatic conditions, but is particularly suited to the lowland tropics with a monsoon climate with a mean annual rainfall of 500-2800 mm with an optimum of about 1000 mm. Under semi-arid conditions (500-700 mm), S. siamea will grow only

SENNA

when its roots have access to groundwater. It requires a mean minimum temperature of 20°C, ranging from 14-28°C, and a mean maximum temperature of 31°C, ranging from 24-36°C. The maximum length of the dry period should not exceed 4-8 months. It is susceptible to cold and frost and does not do well at altitudes above 1300 m. Light requirements are high. S. siamea performs best on deep, well-drained, fertile soils with pH 5.5-7.5, but will grow on degraded, lateritic soils provided drainage is not impeded. It grows poorly on infertile, poorly drained podzolic soils. It is not tolerant of salinity, but is reasonably tolerant ofacid soil conditions. Propagation and planting S. siamea is normally propagated by seed, and plantations are often established by direct seeding. Mature seed has a hard seed-coat and scarification is required. Immersion in concentrated sulphuric acid for 10-30 minutes has been shown to be very effective, although treatment with boiling water is normally sufficient. Using the first method seed germinates for about 90% within 60 days. Germination of untreated seed is about 75% in 4-29 days. Seedlings can be raised in polythene bags in nurseries using standard techniques. Seed should be sown in full light as the slightest shade reduces germination quite considerably. The seedlings are usually transplanted when 25-40 cm tall, about 8-12 weeks after germination. Plants taller than 40 cm should be trimmed before transplanting, to prevent excessive transpiration. Planting density varies according to use. In fuelwood plantations, spacings range from 1m x l(-3) m. In hedges used for alley cropping or as shelterbelt, spacing between plants in the row should be 25-50 cm. S. siamea can be propagated using tissue culture techniques, but this is not a common practice. Husbandry The relatively slow-growing seedlings are susceptible to competition from weeds during early growth. S. siamea needs weeding for the first 1 or 2 years. Cultivation before sowing and the use of selective herbicides (such as fuazifop) helps to reduce weed competition. Alternatively, a broad spectrum herbicide such as glyphosate can be applied in a strip before planting S. siamea to kill grasses and weeds, which then tend to act as a mulch for the young seedlings planted in the centre ofthe strip. Although not N-fixing, S. siamea has been increasingly used in alley-cropping systems, largely because of its coppicing ability and high biomass production. However, a number of studies have

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shown possible competition between S. siamea and associated crops. In Togo, maize yields in rows adjacent to S. siamea hedges were significantly reduced in the area where S. siamea roots dominated the top 0-30 cm of soil. The very extensive root system of S. siamea may prove a disadvantage in alley-cropping systems, unless it can be controlled by careful pruning. The decomposition rate of the leaves is neither fast nor slow. In experiments in Nigeria and in Hawaii, mulching with S. siamea leaves caused initial N-immobilization during 4 weeks. Thereafter, a slight increase in soil mineral nitrogen was found, reaching levels comparable to Leucaena leucocephala and Sesbania sesban (L.) Merrill. Where a mulch is used to control erosion, S. siamea performs better than Grevillea robusta A. Cunn. ex R. Br. because its finer leaves retain water better and also better than Gliricidia sepium, which decomposes more quickly. Diseases and pests No serious diseases or pests have been recorded for S. siamea, but minor damage has occurred in a number of locations. The fungus Phaeolus manihotis occasionally causes damage to the root system. In Indonesia, Ganoderma lucidum is locally a serious disease, causing wood rot on young plants. In Vietnam, the butterfly Catopsylia crocale is a serious pest, its larvae feeding on the foliage. The castor slug caterpillar Parasa lepida has been observed feeding on the leaves of S. siamea in India, while the caterpillar Enerma blanda has caused damage to the terminal buds in plantations in Sri Lanka. Harvesting S. siamea is very tolerant of coppicing, lopping, or pollarding. Plantations can be harvested for fuelwood every 5-7 years, although shorter rotations are often practised in favourable environments. Where mulch or leaf production is the primary aim of a plantation, the first cut may be 12-18 months after sowing, followed by 3-4 cuts per year thereafter. Yield Very high biomass yields can be achieved under favourable conditions. Under irrigation in Karnataka (India) S. siamea was the highestyielding of 13 species with 55.6 t/ha per year. Unirrigated, its yield was 18.7 t/ha per year, second to Acacia auriculiformis A. Cunn. ex Benth. In lowland Nepal it was the most productive species tested, giving a mean annual increment for oven-dry fuelwood of 10 t/ha at 2.5 years of age. Total yields of wood for timber, poles and fuelwood may reach 10-15 m 3 /ha per year. Prospects S. siamea has long been cultivated

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for fuelwood in many tropical countries. It was the most widely used plantation species in Africa in the 1920s and is still highly regarded as a fuelwood because it grows rapidly, coppices well and produces small-size wood, easily handled by smallholder producers. It is worth trying S. siamea as a timber plantation tree. Recently, it has been utilized in sustainable production systems such as alley cropping, and this use will expand. Further studies are required to evaluate its potential as a fodder crop for ruminants. Its relatively high in vitro digestibility, high nutrient content and low fibre content suggest potential in this regard, if the problem of anti-nutritive secondary plant compounds can be overcome. Literature 111Akkasaeng, R., Gutteridge, R.C. & Wanapat, M., 1989. Evaluation of trees and shrubs for forage and fuelwood in northeast Thailand. International Tree Crop Journal 5: 209-220. 121 Blair, G.J., Panjaitan, M., Ivory, D.A., Palmer, B. & Sudjadi, M., 1988. An evaluation of tree legumes on an acid ultisol in South Sumatra, Indonesia. Journal of Agricultural Science (Cambridge) 111: 435-441. 131de Wit, H.C.D., 1955. A revision of the genus Cassia in Malaysia. Webbia 11: 263-265. I4l Gutteridge, R.C, 1990. Agronomic evaluation of tree and shrub species in southeast Queensland. Tropical Grasslands 24: 29-34. I5l Ruhigwa, B.A., Gichuru, M.P. & Spencer, D.S.C., 1994. Economic analysis ofcut and carry and alley cropping systems of mulch production for plantains in south-eastern Nigeria. Agroforestry Systems 26: 131-138. 161 Schroth, G., 1989. Competition between the roots of trees and crop plants in the agroforestry system at Kazaboua, Central Togo. Mitteilungen der Deutschen Bodenkundlichen Gesellschaft 59: 797-802. I7l Tian, G., Kang, B.T. & Brussaard, L., 1992. Biological effects of plant residues with contrasting chemical compositions under humid tropical conditions decomposition and nutrient release. Soil Biology and Biochemistry 24: 1051-1060. I8l Yamoah, C F . , Agboola, A.A. &Wilson, G.R., 1986. Nutrient contribution and maize performance in alley cropping systems. Agroforestry Systems 4: 247-254. 191 Yatazawa, M., Hambali, G.G. & Uchino, F., 1983. Nitrogen fixing activity in warty lenticellate tree barks. Soil Science and Plant Nutrition 29: 285-294. R.C. Gutteridge

Sesbania Adanson Fam. pi. 2: 326 (1763) (Sesban), corr. Scopoli, Intr.: 308 (1777), nom. cons. LEGUMINOSAE - PAPILIONOIDEAE

x =6;S. bispinosa: 2n = 12, 14, 24;S. cannabina: 2« = 12;S. sericea: 2n = 12, 24 Major species and synonyms - Sesbania bispinosa (Jacq.) W.F. Wight, U.S. Dept. Agr. Bur. PL Ind. Bull. 137: 15 (1909), synonyms: Aeschynomene aculeata Schreb. (1770), A. bispinosa Jacq. (1792), Sesbania aculeata (Willd.) Pers. (1807). - Sesbania cannabina (Retz.) Poiret, Encycl. 7: 130 (1806), synonyms:Aeschynomene cannabina Retz. (1789), Sesbania australis F. Mueller (1855). - Sesbania rostrata Bremek. & Oberm. - see separate article. - Sesbania sericea (Willd.) Link, Enum. Hort. Berol. 2: 244 (1822), synonyms: Coronilla sericea Willd. (1809), Sesbania pubescens DC. (1825), S. polyphylia Miq. (1855). Vernacular names General: Sesbania (En). Sesbane (Fr.) - S. bispinosa: Prickly sesban, sesbania pea (Australia)(En). Laos: sanô: (general), sanô s'a:ngz (Louang Prabang), kho:ng kh'wa:y (Houa Phan). Thailand: sano-khangkhok (central). Vietnam: r[us]t (Hanoi, Thanh Hoa), (c[aaly) di[eef]n di[eex]n, di[eef]n s[ooj]i. - S. cannabina Yellow pea bush (Australia), dhaincha (India) (En). Sesbane chanvré (Fr). Malaysia: turi. Philippines: balakbak (Tagalog), ganai (Bisaya), rubau (Ilokano). - S. sericea: Malaysia: turi. Vietnam: (c[aa]y) di[eef]n di[eef]n. Origin and geographic distribution Sesbania comprises about 50 species and occurs throughout the tropics and subtropics; it is richest in Africa. S. bispinosa is widespread from Africa and Madagascar, through India and Pakistan to China and South-East Asia; although its origin is unknown it is thought to have been introduced in much ofits range. S. cannabina occurs naturally in Australia, Papua New Guinea and eastern Indonesia. It is probably introduced in other areas of South-East Asia and in South Asia (from India up to Iraq) and is also cultivated in other tropical areas. S. sericea occurs in tropical Africa and southern Arabia, China, Indo-China, Thailand, Java and New Guinea. It was introduced into the West Indies and northern South America. U s e s Sesbania yields light, small sized firewood,

SESBANTA

while green branches and leaves are used as green manure in the production of food crops, especially rice. In north-eastern India, it is also widely grown as green manure in tea estates. Sesbania is planted as temporary shade and grown as hedges, it is also used as a wind-break. Shade plants and wind-breaks also provide seed for green manure crops. The stems ofS. bispinosa and S. cannabina yield a phloem fibre used mainly in northern India as a substitute for sunn hemp (Crotalaria juncea L.) or jute (Corchorus spp.) in making ropes, cordage for fish nets, and sails; the fibre is also used in paper manufacture. The leaves are used as fodder. A galactomannan gum obtained from the seed is used as a substitute for gum from Cyamopsis tetragonoloba (L.) Taubert. In traditional medicine, seed mixed with flour is used for treatment of ringworm and other skin diseases and wounds. Properties The green parts of S. sericea contain per 100 g approximately: water 82 g, crude protein 4.5 g, ether extract 0.7 g, N-free extract 6.8 g, crude fibre 4.3 g, ash 1.6 g, P 0.05 g, Ca 0.2 g. The composition of the seed approximates per 100 g: crude protein 35 g, ether extract 5 g, N-free extract 45 g, crude fibre 11 g, ash 5 g, P 0.6 g, Ca 0.4 g. The fibre is suitable for making paper. The endosperm of the seed contains per 100 g 25-30 g gum made up of galactose and mannose in the approximate proportion 1:1.5. It is water-soluble and produces a smooth, light coloured, coherent and elastic film used for sizing textiles and paper products and for thickening and stabilizing solutions. Description Erect annual, or short-lived perennial, herbs or slightly woody shrubs or small trees, often producing a dark gummy juice when the bark is cut. Hairs simple, white or golden. Leaves paripinnate; leaflets often more than 10 pairs. Inflorescence an axillary or terminal raceme; bracts and bracteoles often early caducous; calyx campanulate with 5 subequal teeth; corolla glabrous, blue, mauve, white, red or orange, or more commonly yellow; standard usually streaked and spotted or continuously veined with purple, the claw with two vertical parallel or divergent variously shaped appendages; wings with transverse lamellate sculpturing, usually toothed or hooked at the base, the claw much shorter than the blade and than that ofthe keel; keel rounded below, rounded or broadly pointed at the tip, usually toothed at the base, shorter or slightly longer than the claw; stamens 10, diadelphous, vexillary stamen free, bent sharply near the base; pistil subglabrous;

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stigma small, globose or ovoid. Fruit a usually long pod, dehiscent, rostrate, usually stipitate, sometimes winged, transversely septate, up to 50seeded. Seed usually ellipsoid or cylindrical, hilum often surrounded by a narrow rim-aril. Seedling with epigeal germination; first leaf entire. - S. bispinosa. Herb, (0.6-)l-3 m tall. Stem terete, glabrous or sparsely pilose when young, usually aculeate. Leaves (5.5-)9.5-29.5(-35) cm long; stipules 5-11 mm long, pilose on margins and above, late caducous; petiole 2-20 mm long; leaflets in (10-)20-50(-55) pairs, oblong to oblong-linear, 0.75-2(-2.6) cm x 1.5-3(-5) mm, base obtuse, apex obtuse, emarginate, usually apiculate, glabrescent. Raceme (l-)2.5-15(-16.5) cm long, l-12(-14)-flowered; peduncle (0.5-)1.54(-6) cm long, glabrous; calyx 3-4 mm x 3-4 mm, tube glabrous except for woolly margins, teeth triangular, 0.5-1 mm long; corolla yellow; standard rounded to obovate, 1-1.5 cm x 8-14 mm, pale yellowish, spotted brownish or purplish; wings oblong, 1-1.25 cm x 2.5-3 mm, yellow; keel straight, 1-1.3 cm x 3.5-5 mm; staminal tube up to 12 mm long, free filament parts 2-4 mm long; pistil glabrous, style 2-3 mm long, stigma capitate. Pod 28-45-seeded, curved, 12.5-25 cm x 2-3 mm, glabrous, constricted between the seeds. Seed ellipsoid, 3 mm x 1.5 mm x 1.2 mm, pale brown, olive-green or greenish-black. - S. cannabina. Annual slender subshrub, up to 3.5 m tall. Stem terete, slightly striate, glabrescent. Leaves with 10-45 pairs of leaflets; stipules linear-lanceolate, up to 6 mm long, ciliate; petiole 3-15 mm long; rachis sparsely hairy; stipels subulate with gland-like tips; leaflets oblong-obtuse or truncate-apiculate or mucronate, 8-25 mm x 3-4 mm, glabrous or sparsely sericeous especially on prominent midrib on lower surface. Raceme about 6 cm long, 4-12-flowered; peduncle about 1 cm long; pedicel slender, shorter or a little longer than the calyx; calyx 3-5 mm long; corolla yellow or orange-yellow; standard transversely oblong-orbicular, 13 mm x 15 mm, conspicuously streaked on back, pale within, claw flat and short, not thickened; wings about as long as the standard; keel slightly shorter than the wings; pistil glabrous. Pod very slender, 12-20 cm x 2.5-4 mm, curved or almost straight, more or less torulose when young, hardly so when mature, olive-green to brown, with darker, transverse markings corresponding to the septa. Seed cylindrical, about 3 mm x 1.7 mm, dark brown, shiny.

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Sesbania sericea (Willd.) Link - 1,habit; 2, flowering and fruiting branch; 3, leaflet; 4, flower; 5, pod; 6,seed in fruit. - S. sericea. Herb or subshrub, 1-3 m tall, striate and pubescent throughout except for the flower and fruit, silky when young. Stem often with minute prickles hidden amongst the hairs but not obviously aculeate, exuding bluish, slightly milky juice after cutting. Leaves with 20-25 pairs of leaflets; stipules linear-lanceolate, up to 6 mm long, very early caducous; petiole 0.5-3 cm long; rachis 10-15 cm long; leaflets linear-oblong, up to 2 cm x 4 mm, rounded at apex, apiculate, entire. Raceme lax, axillary, 1-9 cm long, 2-7-flowered; peduncle up to 2 cm long, softly silky or pilose; pedicel 3-8 mm long, sparsely silky pilose; calyx 3-4 mm x 3 mm, tube glabrous, teeth triangular, up to 0,7 mm long; corolla yellow; standard elliptical, 6-9 mm x 8-10 mm, broader than long, pale cream, slightly flecked violet or purple; wings obovate, 5-9 mm x 3-4.5 mm; keel 7-8 mm x 4-6 mm. Pod 15-30-seeded, straight or slightly curved, up to 16 cm x 2.5-3.5 mm, not torulose, brown, glabrous. Seed 3 mm x 2 mm x 1.5 mm, brown to reddish-brown, with tiny blackish spots. Growth and development Sesbanias are nor-

mally spreading shrubs, but in dense stands they are less branched. They grow very rapidly and may reach a height of over 3.5 m in 6 months, making them very competitive with weeds. Root nodules that effectively fix atmospheric nitrogen are formed with Rhizobium. Under waterlogged conditions, the submerged part of the stem forms a spongy mass of aerenchyma. Sesbania can produce a green manure crop in 2-3 months and a fuelwood crop in 5-6 months. Leaves of sesbania follow the direction of sunlight and fold at night. The flowers are mainly pollinated by bees. Ripe pods normally do not shatter and harvesting of seed can be delayed for several months, although pods will shatter eventually and may be damaged by insects. Other botanical information The taxonomy of the 3 species treated here is very confused and in the agronomic literature it is often impossible to attribute information unequivocally to a single species. The differences between S. bispinosa and S. cannabina in particular are small and can mainly be found in the morphology of the keel. S. cannabina has sometimes been included in S. bispinosa and also in S. sericea. The variability of the 3 species is great, many varieties have been described, but often a clear distinction cannot be made. Only a thorough, worldwide revision of the genus might bring clarity. In South-East Asia other Sesbania species occur with similar uses, e.g. S. grandiflora (L.) Poiret, S. sesban (L.) Merrill and S.javanica Miquel. Ecology Most Sesbania species are found in seasonally wet habitats in the tropics and subtropics. S. bispinosa grows along waterways, in marshes, often on disturbed sandy soils, from sea level to 1100 m altitude, in areas with an annual rainfall of up to 1200 mm. S. cannabina grows in wet areas like river beds and irrigated rice fields, up to 50 m altitude. S. sericea is tolerant of high temperatures, at least up to 40°C, but does not tolerate even light frost. It is found up to 1250 m altitude, in Indo-China to 850 m. S. sericea grows best in locations with an annual rainfall of 500-2000 mm, is tolerant of waterlogging and also very tolerant of drought. It is adapted to clayey, moderately acid and alkaline soils. In trials in India, growth was retarded in soils with pH 5.6 and 9.3. Under irrigated conditions, sesbania, like rice, can tolerate fairly high concentrations of sodium (ESP >50). Propagation and planting Sesbania is propagated by seed. No seed treatment is required for S. bispinosa, S. cannabina and S. sericea. When

SESBANIA

grown as sole crop for green manure, seed requirements per ha are about 90-100 kg when broadcast, or 20-60 kg when drilled in rows. Dense stands are used to obtain tender plants for green manure. When grown as a green manure for rice, several cropping systems are used, mainly depending on the availability of time and labour. When the growing season is long enough, sesbania is grown as a sole crop in rotation with rice. This method is the least labour intensive. When time interval between rice crops is short and sufficient labour is available, sesbania is either relay sown into the standing rice crop, or even sown in a nursery and transplanted. Relay sowing is reported from northern Vietnam and southern China, transplanting from southern China. When the time interval between rice crops is even shorter, sesbania may be grown as a cut and carry green manure on field bunds or outside the paddy fields. When the water level in the rice paddy is too high for relay sowing, mounds are made at a spacing of about 100 cm x 50 cm in between the rice rows with the tops of the mounds just emerging above the water. About 3-5 seeds are sown in these mounds 6 weeks before harvesting the rice crop. Husbandry Because of its very fast growth, sesbania competes very well with weeds and may even suppress Imperata cylindrica (L.) Raeuschel on sites where moisture is adequate. In some areas, it is considered a weed. When grown for green manure, S. sericea is either grown in situ or in nearby fields, field bunds or waste areas to be transported and dug in the field. Decomposition of sesbania after ploughing in is rapid. As green manure it can be ploughed in just before transplanting rice. Delaying transplanting may result in a lower response to the green manure. Rice yields after a sesbania green manure crop ploughed in 60-70 days after planting are about equal to those obtained with application of about 80 kg N/ha of chemical fertilizer (on average 4.3 t/ha, compared with 3.3 t/ha without fertilizer or green manure). This is lower than has been obtained with S. rostrata. Sesbania is considered easier to grow than Azolla pinnata R. Br., but cultivated as an intercrop it competes more with the rice crop. In Vietnam, sesbania planted as a green manure crop is sometimes left to mature and produce firewood when the rains are inadequate to produce a rice crop. In Taiwan, S. sericea is grown in the interrows in banana plantations, and sown at the time of planting banana. The legume is later cut and spread out as a mulch to control weeds and used as green manure. In the foothills ofthe Himalayas

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in northern India, S. sericea is sown as a green manure in ginger (Zingiber officinale Roscoe) fields. They are progressively thinned from around the ginger plants to provide green manure or mulch, but a few plants, spaced 2-3 m apart are left to provide a light shade. Intercropping S. sericea with maize to provide green manure for a subsequent wheat crop has been tried in India. When sown simultaneously with the maize, S. sericea smothered the maize; delaying sowing S. sericea by 6 weeks did not depress the maize yield and boosted the following wheat yield by about 20-40%. In India, growing S. sericea is often combined with applications of gypsum to improve saline-sodic soils. Diseases and pests Damage caused by diseases is generally of limited and local importance only. A number of insect pests affect the leaves and stems, but damage is mostly minor. References to seed pests are very few, although large amounts of seed are produced and stored in India. Yield S. sericea can produce large amounts of organic matter in a short period. In Hawaii, several selections produced over 15 t dry matter per ha in 14 weeks, about half of it in stems. In India, sesbania grown as a sole crop produced 20-30 t/ha fresh above-ground biomass (4-6 t dry matter, containing 60-100 kg N) in 60 days. In the Philippines, the reported yields of sesbania in 60 days were even higher (7.8-9.9 t/ha of dry matter containing 170-225 kg N). Handling after harvest To extract the fibre of S. cannabina, stems are submerged in water for about 25 days. When fully retted, the bast is removed manually and the fibre is cleaned and dried. Genetic resources and breeding The Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia maintains the largest collection of Sesbania germplasm, including many accessions from Australia. Other collections are maintained at the International Rice Research Institute, Los Bafios, the Philippines, and the Institut français de Recherche Scientifique pour le Développement en Coopération, Office de la Recherche Scientifique et Technique Outre-Mer (ORSTOM), Dakar, Senegal. A small collection is maintained in the United States at the Department ofAgronomy and Soil Science, University of Hawaii and at the Southern Regional Plant Introduction Station, Griffin, Georgia. No breeding programme is known. Prospects Sesbania deserves wider attention as a green manure and firewood crop. It grows

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very rapidly, is tolerant to adverse soil conditions, waterlogging and moisture stress. Plant biomass decomposes rapidly after being ploughed in. Although the wood is light, large quantities are produced in a very short time. A worldwide taxonomierevision is urgently needed. Literature 111Burbidge, N.T., 1965. The Australian species of Sesbania Scopoli (Leguminosae). Australian Journal of Botany 13: 103-141. 121 Evans, D.O. & Rotar, P.P., 1987. Sesbania in agriculture. Westview Tropical Agriculture Series, Westview Press, Boulder, United States. 192 pp. 131Gillett, J.B., 1963. Sesbania in Africa (excluding Madagascar) and southern Arabia. Kew Bulletin 17: 91-159. 141 Lock, J.M. & Heald, J., 1994. Legumes of Indo-China, a check-list. International Legume Database and Information Service (ILDIS). Royal Botanic Gardens, Kew, United Kingdom, pp. 126-127. 15! National Academy of Sciences, 1980. Firewood crops; shrub and tree species for energy production. Vol. 1. National Academy Press, Washington, D.C., United States. pp. 60-61. 161 Nguyen Van Thuan, 1987. Sesbania. In: Lescot, N. &Vidal, Y. (Editors): Flore du Cambodge, du Laos et du Vietnam. Vol. 23. Leguminosae (Fabaceae) Papilionoideae. Muséum National d'Histoire Naturelle, Paris, France, pp. 56-62. 171 Pareek, R.P., Ladha, J.K. & Watanabe, I., 1990. Estimating N 2 fixation by Sesbania rostrata and S. cannabina (syn. S. rostrata) in lowland rice soil by the l5 N dilution method. Biology and Fertility of Soils 10:77-88.

old S. rostrata grown in northern India contained per 100 g dry matter: N 2.9 g, P 0.3 g, K 1.6 g, S 0.4 g. Description Erect, robust, softly woody, nonaculeate annual or short-lived perennial, 1-3 m tall. Stem pithy, sparsely pilose, glabrescent, with vertical rows ofpustules usually evident above the leaf axils and producing warty outgrowths on older stems, submerged portions clothed with matted fibrous roots. Leaves paripinnate, (4.5-)7-25 cm long; stipules linear-lanceolate, 5-10 mm long, reflexed, pilose, very persistent; petiole 3-8 mm long, pilose; rachis up to 19 cm long, sparsely pilose; stipels present at most petiolules; leaflets opposite, in (6-)12-24(-27) pairs, oblong, 0.9-3.5 cm x 2-10 mm, the basal pair usually smaller than the others, apex rounded to obtuse to slightly emarginate, margins entire, glabrous above, usually sparsely pilose on margins and midrib beneath. Inflorescence an axillary raceme, shorter than subtending leaf, 1-6 cm long, (l-)3-12(-15)flowered; rachis pilose; peduncle 4-15 mm long, pilose; pedicel 4-15(-19) mm long, sparsely pilose; bracts and bracteoles linear-lanceolate, 5-8 mm long, sparsely pilose, caducous; calyx campanu-

LB. Ipor &L.P.A. Oyen

Sesbania rostrata Bremek. & Oberm. Ann. Transvaal Mus. 16:419 (1935). LEGUMINOSAE - PAPILIONOIDEAE

2ra= 12 Synonyms Sesbania pachycarpa DC. (1825) pro parte, S. hirticalyx Cronquist (1952). Vernacular n a m e s Sesbania (En). Origin and geographic distribution S. rostrata occurs naturally throughout tropical Africa. It is cultivated, mainly on experimental scale, in West Africa and East and South-East Asia. Uses S. rostrata is used as green manure in wetrice cultivation. It has also shown potential for incorporation in alley-cropping systems. It is suitable as a fodder for both ruminants and non-ruminants. The leaves are processed into leaf meal. Dry stems are used as fuel e.g. in Madagascar. Properties The above-ground parts of 50 days

Sesbania rostrata Bremek. and fruiting branch.

Oberm. - flowering

SESBANIA

late, 5-7.5 mm x 4-5 mm, sparsely pilose, teeth 1-2 mm long, subulate, sparsely pilose; standard suborbicular, 12-16(-18) mm x 11-14(-15) mm, yellow or orange, speckled dark purple or reddish, apex emarginate, appendages with short, triangular, upward-pointing or slightly incurved, free tips, less than 1 mm long; wings 13-17 mm x 3.5-5 mm, yellow, a small triangular tooth and the upper margin of the basal half of the blade together characteristically inrolled; keel 12-17 mm x 6.5-9 mm, yellow to greenish, basal tooth short, triangular, slightly upward-pointing with small pocket below it on inside ofthe blade; stamens 10, vexillary stamen free, bent sharply near the base, staminal sheath longer than free parts of filaments, auricled; ovary sparsely pilose on upper margin or glabrous, style glabrous, stigma small. Pod in outline falcate, 15-22 cm x 3.5-5 mm, beak slender, up to 3.5 cm long, thicker at the centre than at the sutures, up to 50-seeded. Seed subcylindrical, 3-3.5 mm x 2.5-3 mm x 2-2.5 mm, brown, greenish or dark reddish-brown; hilum in a small, central, circular pit. Growth and development Under favourable conditions, S. rostrata grows very fast, reaching a height of 2 m in 60 days, accumulating 8-11 t above-ground dry matter per ha. S. rostrata nodulates with three groups of rhizobia. Stem nodules are formed following infection with strains ofAzorhizobium caulinodans such as TCSR-1 and ORS-571. This symbiosis is highly specific. A. caulinodans differs from Rhizobium and Bradyrhizobium strains in its ability to fix atmospheric nitrogen as a free-living organism and is closely related to Xanthobacter. A. caulinodans may infect many Sesbania species, but forms an effective symbiosis almost exclusively with S. rostrata. A second group of rhizobia belongs to Rhizobium and forms root nodules only; it infects and fixes atmospheric nitrogen in symbiosis with many Sesbania species. The third group comprises a few strains of Rhizobium and forms effective stem and root nodules in S. rostrata and only root nodules in several Sesbania species. Information on the ability of S. rostrata to fix atmospheric nitrogen in the presence of soil nitrogen is conflicting. Some studies indicate that nodule numbers and N-fixation rate are only slightly reduced by soil nitrogen and N-fertilizer applications of up to 100 kg/ha. Other studies have found a reduction in the number of stem nodules proportional to the N-fertilizer gift, and no formation of root nodules. Acetylene reduction assays have indicated that the rate of nitrogen fixation of stem nodules was

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reduced to only 10% of the unfertilized control by an N-fertilizer application of 30 kg/ha, and to even lower levels with higher applications up to 60 kg/ha. Plant height and fresh weight, however, were highest with 30 kg N-fertilizer per ha. S. rostrata is a quantitative short-day plant, with a critical photoperiod of 12-12.5 hours. Other botanical information S. rostrata is one of the 3 taxa of Sesbania Adanson that form stem nodules, the others being S. speciosa Taubert from East Africa, cultivated and naturalized in Indonesia and New Guinea and S. sesban (L.) Merrill var. punctata (DC.) J.B. Gillett (synonym: S. punctata DC.) from tropical Africa. Ecology S. rostrata occurs naturally in marshes, floodplains, on muddy river banks and the edges of pools, but has also been recorded in open savanna. It occurs up to 1600 m altitude and tolerates waterlogged soils and flooding to over 1 m deep. In cultivation, S. rostrata is almost always associated with wet rice. Propagation and planting S. rostrata is mainly propagated by seed. Treatment of seed with concentrated sulphuric acid for 30 minutes improved the germination rate to more than 90%. Subsequently, treated seed should be washed with ample water to avoid overheating. Scrubbing seed with sand, or a hot water treatment are much less effective. Seed is broadcast, requiring 40-60 kg/ha. S. rostrata is either planted in rice paddies or on the bunds of rice fields and waste land near rice fields. Vegetative propagation by stem cuttings is possible, as the nodulation sites on the stems consist of adventive root primordia. Using of cuttings instead of seed results in a quick establishment of the crop and may double the N accumulation in a 6-week growth period, or reduce the growth period by 2 weeks. It is only necessary to apply a solution of an appropriate Rhizobium strain in locations where S. rostrata has not been grown before. Spontaneous inoculation in the field is generally adequate for a high rate of nitrogen fixation. Although Rhizobium strains for stem inoculation are highly specific, they are easily established in the soil, as they can be transferred via the seed-coat. They show a high rate of survival under flooded and dry conditions. Natural infection of stems probably occurs through wind, rain splash and insects. Husbandry Grown as a green manure crop, S. rostrata is allowed to grow for 45-65 days depending on its growth rate. When it is left to grow longer than about 55 days, the lignin content increases which decreases the decomposition rate of

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AUXILIARY PLANTS

plant biomass. During the short-day season, it may be left to grow longer as it starts flowering early, resulting in a lower growth rate. The green manure crop is ploughed in just before the rice crop is sown or transplanted. Initial decomposition is rapid, with 30-45% of the leaf material decomposing in 10 days after incorporation. Decomposition then slows down considerably, reaching 50% after 35 days, while the half-life of stems and root-stubble is about 110 days. When S. rostrata is grown for green manure, applying P and K fertilizers at the rate normally given to rice may increase nitrogen fixation by 30% and improve the availability of N, P and K to the subsequent rice crop. At the International Rice Research Institute, Los Banos, the Philippines, the average rice grain yield was about 6 t/ha after incorporation of a S. rostrata crop grown for 45-60 days, which is the same as the yield obtained with urea applied at a rate of 50-60 kg N/ha. Under favourable conditions the amount of N accumulated in the green manure crop is about 100 kg/ha in 50 days and 160 kg/ha in 60 days. The residual effect of Sesbania green manure application on soil organic matter and N levels seems limited. It has been proposed to plant S. rostrata on field bunds. Prunings of these plants would provide cuttings for vegetative propagation, or be a source of readily available green manure. These plants could also be a source of seed. Diseases and pests The most common diseases affecting S. rostrata are damping-off caused by Pythium spp. and Rhizoctonia spp., leaf spot caused by Cercospora spp. and viral leaf mosaic. The root-knot nematode Meloidogyne attacks the root system. In dry conditions of the West African Sahel, nematode attack may be so serious that it is impossible to grow S. rostrata. Genetic resources and breeding Germplasm collections of Sesbania are maintained at the International Rice Research Institute, Los Banos, the Philippines, by the Institut de Recherche Scientifique pour le Développement en Coopération, Office de la Recherche Scientifique et Technique Outre-Mer (ORSTOM), Dakar, Senegal, and by the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia. A small number of accessions is maintained at the Southern Regional Plant Introduction Station, Griffin, Georgia, the United States. No breeding programme is known to exist. Prospects Stem-nodulating legumes such as S. rostrata have a high potential as green manure in

wet-rice production systems, because of their very fast growth and high rate of atmospheric nitrogen fixation, especially under wet conditions. Its tolerance of flooding gives S. rostrata a competitive advantage over most other legumes. Selection of cultivars resistant to diseases is urgently needed. Literature 111 Alazard, D., Ndoye, I. & Dreyfus, B., 1988. Sesbania rostrata and other stem-nodulated legumes. In: Both, H., de Bruijn, F.J. & Newton, W.E. (Editors): Nitrogen fixation: hundred years after. Gustav Fisher, Stuttgart, Germany, pp. 765-769. I2l Becker, M., Diekmann, K.H., Ladha, J.K., De Datta, S.K. &Ottow, J.C.G., 1991. Effect of NPK on growth and nitrogen fixation of Sesbania rostrata as a green manure for lowland rice (Oryza sativa L.). Plant and Soil 132: 149-158. 13! Becker, M., Ladha, J.K. & Ottow, J . C G , 1988. Stem-nodulating legumes as green manure for lowland rice. Philippine Journal of Crop Science 13: 121-127. I4l Buresh, R.J., Garrity, D.P., Castillo, E.G. & Chua, T.T., 1993. Fallow and Sesbania effects on response of transplanted rice to urea. Agronomy Journal 85: 801-808. 151 Joshua, D.C., Saradha Ramani, Suarez, E. & Shaikh, M.S., 1992. Growth, stem nodulation, and nitrogen content of Sesbania rostrata plants treated with different rates of urea. Journal of Plant Nutrition 15: 1353-1358. 161 Lewis, G.P., 1989. Sesbania Adans. in the Flora Zambesiaca region. Kirkia 13:32-34. 171 Pandey, R.K., 1991.A primer on organic-based rice farming. International Rice Research Institute, Manila, the Philippines. 201 pp. 181Ventura, W. & Watanabe, I., 1993. Green manure production ofAzolla microphylla and Sesbania rostrata and their long-term effects on rice yields and soil fertility. Biology and Fertility of Soils 15:241-248. LB. Ipor

Sonneratia ovata Backer Bull. jard. bot. Buitenzorg, Série 3, Vol. 2: 329 (1920). SONNERATIACEAE

2« = 22 Synonyms Sonneratia alba auct., non J. Smith (1819). Vernacular n a m e s Sonneratia (En). Brunei: perapat. Indonesia: bogem (Palembang), kedabu (East Sumatra). Malaysia: gedabu (Peninsular Malaysia), (pedada) rogam (Sarawak). Cambodia: ampea, lapea. Thailand: lamphaen. Vietnam: b[aaf]n [oor]i,b[aaf]n h[oo]i.

SONNERATIA

Origin and geographic distribution S. ovata is found scattered in widely separate localities from China and Thailand through Peninsular Malaysia, the Riau Archipelago, Java, and Borneo, to Sulawesi, the Moluccas, and Daru Island and Milne Bay in New Guinea. References to its occurrence in Queensland and the Northern Territory in Australia have been disclaimed. It is locally numerous, but on the whole rather rare. Uses The wood of S. ovata serves as firewood. As a timber it is ofvery limited value. S. ovata can be used to control erosion of tidal river banks. Like other Sonneratia spp., the bark contains tannin, but in amounts too small for commercial exploitation. The fruits are edible, though they taste very sour. Because of their acidity they are sometimes used as substitutes for vinegar. The fruit is also applied in poultices to relieve sprain. The fermented juice is believed to check haemorrhages. Properties The wood of S. ovata has been described as moderately hard to very hard and moderately heavy to heavy. Its pulping qualities have yet to be tested; the wood of the related species S. caseolaris (L.) Engler can be pulped by a sulphate process to give a pulp with strength properties similar to commercial eucalypt pulp. The wood of Sonneratia L.f. has retained many protomyrtalean characters. One primitive feature is the rudimentary presence of scalariform and reticulate perforation plates in the wood structure. Growth rings are distinct, mainly delimited by radially flattened fibres. Parenchyma is absent, fibres are septate, with 2-3 septa per fibre. Botany Columnar tree, up to 2-5(-20) m tall, with stem up to 20 cm in diameter. Stem short and usually twisted, base not buttressed, surrounded by thin, pointed, pneumatophores about 20 cm long. Bark grey, smooth to slightly fissured, lenticellate, inner bark pale brown to reddish, faintly laminated, rather watery. Sapwood pale yellow, soft. Twigs distinctly jointed above the nodes, quadrangular when young, terete with age, greyish brown. Leaves simple, opposite, exstipulate; petiole 2-15 mm long; blade usually ovate to orbicular or broadly ovate, 4-10 cm x 3-9 cm, base rounded or subcordate, apex broadly rounded, upper surface glossy, slightly corrugated with 9-16, fine but conspicuous lateral veins. Flowers bisexual, usually in terminal groups of 2-3(-4), occasionally solitary; pedicel 1-2 cm long, sometimes absent; buds broadly ovoid, apex rounded or obtuse, finely verruculose, 1.5-3 cm x 1-1.5 cm; calyx persistent, calyx tube cup-shaped, tapering abruptly into a stalk-like base, ribbed segments usually 6,

Sonneratia ovata Backer

243

1, flowering branch; 2,

fruit. ovate-triangular, 13-15 mm long, inner surface markedly reddish cream at base; petals absent or vestigial; stamens many, filaments about 2 cm long, white, anthers yellow; ovary 10-15-celled, style about 2.5 cm long. Fruit an indéhiscent, flattened globose berry, resting on the calyx-tube, 3-5 cm in diameter, 2-3 cm thick, dark green when young turning yellowish-green when ripe. Seeds numerous, rounded, irregular, about 5 mm long, embedded in foul-smelling pulp; embryo straight. Hybrids between S. ovata, S. alba J. Smith and S. caseolaris (L.) A. Engler have been found in the estuary of Brunei, where they grow together. Normally they are ecologically separated, S. ovata growing closest to the land-side. Diagnostic field characteristics for S. ovata are the broadly ovate leaves without mucro, the verruculose calyx surface, the appressed calyx lobes in fruit, the absence of petals, the white filaments and the rounded irregular seeds. Its flowers are ephemeral and open at sunset, lasting for only one night; stamens fall off in the early morning. Bats and nectar-feeding birds are the pollinators. In Papua

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New Guinea, S. ovata flowers from March to October, and fruits are ripe in April-December. In Vietnam it flowers in March-April and bears mature fruits in June-July. Ecology S. ovata is occasionally found on the banks of tidal creeks and rivers, on muddy soils inundated only by spring tides. Fruits float, so water is the normal means of dispersal. It is found as individual trees, scattered among other mangrove species, such as Excoecaria agallocha L. S. ovata has never been found forming pure stands similar to S. alba and has also never been recorded from coral reefs. Agronomy Although S. ovata mostly grows wild, it is cultivated for its fruits and as an ornamental in some villages in coastal Sarawak. Propagation is by seed. Prospects Although the wood of S. ovata is used as firewood, it is not sought after. S. ovata may be used to control erosion along tidal river banks. S. ovata will probably remain ofvery limited economic importance. Literature 111 Ashton, P.S., 1988.Manual of the non-dipterocarp trees of Sarawak. Vol. 2. Dewan Bahasa dan Pustaka, Kuala Lumpur, Malaysia, p. 380. 121 Backer, C.A. & van Steenis, C.G.G.J., 1951. Sonneratiaceae. In: van Steenis, C.G.G.J. (Editor): Flora Malesiana, Series 1,Vol. 4. Noordhoff-Kolff, Jakarta, Indonesia, pp. 280-289. 131 Duke, N.C. &Jackes, B.R., 1987. A systematic revision of the mangrove genus Sonneratia (Sonneratiaceae) in Australasia. Blumea 32: 277-302. I4l Muller, J. & Hou-Liu, S.Y., 1966. Hybrids and chromosomes in the genus Sonneratia (Sonneratiaceae). Blumea 14: 337-343. I5l Rao, R.V., Sharma, B., Chauhan, L. & Dayal, R., 1987. Reinvestigation ofthe wood anatomy of Duabanga and Sonneratia with particular reference to their systematic position. IAWA (International Association of Wood Anatomists) Bulletin (new series) 8(4): 337-345. 161 Voon Boon Hoe, Sim, P. &Chin Thian Hon, 1988. Sayur-sayuran dan buah-buahan hutan di Sarawak [Vegetables and fruits from the forest in Sarawak]. Department of Agriculture, Sarawak, Malaysia. 55 pp. B. Othman

T e p h r o s i a Candida (Roxb.) DC. Prod. 2:249(1825). LEGUMINOSAE - PAPILIONOIDEAE

2« = 22 Synonyms Kiesera sericea Reinw. (1828), Robi-

nia Candida Roxb. (1832), Xiphocarpus candidus (Roxb.) Endl. ex Hassk. (1843). Vernacular n a m e s White tephrosia (En). White hoary pea (Am). Indigo sauvage (Fr). Indonesia: enceng-enceng (Javanese), kapeping badah (Sundanese), poko torn (Sumatra). Papua New Guinea: pis pea (Pidgin). Origin and geographic distribution T. Candida is native to the tropical foothills of the Himalayas in India, and is cultivated and naturalized throughout South-East Asia, from India and Sri Lanka through Burma (Myanmar), Indo-China, Malaysia, Indonesia, the Philippines and Papua New Guinea to the Solomon Islands, New Zealand and Hawaii. It has also been introduced in the West Indies and South America and has been tested in Africa. Uses T. Candida is grown for many auxiliary purposes. It rehabilitates degraded land and controls erosion. During the first few years after planting it is used as a green manure crop; when it becomes woody with age it provides fuelwood. In newly planted perennial crops such as citrus, coconut, coffee, rubber and tea, it is grown as a temporary shade crop and later for filling in gaps for erosion control. It is said to improve the quality and yield of tobacco. In Vietnam, it is planted as a green manure in rotation or intercropped with annual crops. It is suitable for making hedges along contours, around fields and home gardens, as it is not eaten by domestic animals such as buffaloes and goats. There are unconfirmed reports of the bark and roots being used as fish poison. Powdered leaves are used as insecticide. T. Candida is occasionally grown as an ornamental. Properties The approximate composition of dry leaves of T. Candida per 100 g is: N 2.4-3.8 g, P 0.12 g, K 1.15 g, Ca 0.3 g; of the roots: N 1.18 g, P 0.07 g, K 0.47 g, Ca 0.14 g. The seeds and leaves contain small amounts ofrotenoids, tephrosin and flavonoids. Description Herb, shrub or small tree, erect with straggling branches from base, up to 3.5 m tall. Leaves spirally arranged, imparipinnate; stipules 5-11 mm x 0.8-1.5 mm, often caducous; rachis (including the petiole) up to 22.5 cm long, with brown indumentum, pulvinate at base; petiolule 1.5-4 mm long, pulvinate; leaflets 6-13 pairs, opposite, narrowly ovate, elliptical to narrowly obovate, 1.3-7.5 cm x 0.5-1.7 cm, glaucous green, soft, with silvery indumentum, base acute, apex acute, long-mucronate, venation distinct below. Inflorescence a terminal, axillary or leaf-opposed pseudoraceme, 2.5-40 cm long; basal bracts

TEPHROSIA

few, leaf-like, upper bracts narrowly triangular, 2.2-6 mm x 0.5-1.5 mm, often caducous; flowers in fascicles of 5-13; bracteoles triangular, smaller than bracts, sometimes caducous; pedicel 9-16 mm long; flower 13-26 mm long, white, silky, with dark brown hairs on the outside; calyx campanulate, unequally 4-toothed, cup fleshy, 3-4 mm x 4.5-7 mm, green, sericeous, teeth deltoid, sericeous outside, glabrescent, pubescent to sericeous inside; standard broadly ovate to obovate, 13-25 mm x 11-25 mm, apex rounded to emarginate, acuminate, claw 1-5 mm long; wings 12-20 mm x 5.5-13 mm, glabrous, claw 1-4.4 mm long; keel 11-20 mm x 3-10 mm, glabrous, lateral pockets sometimes bulging, claw 1.5-5 mm long; stamens 10, auricled, staminal tube 8-20 mm long, glabrous, vexillary filament free at base, connate halfway, other filaments alternately longer and shorter, free part 3 mm long; pistil with bearded style of up to 11 mm long, stigma penicillate at base. Pod linear, 7-12 cm x 0.5-1 cm, green or brown with silky hairs, slightly convex around the 10-15 seeds. Seed broadly ovoid, 4-5.5 mm x 3-4 mm, brown or greyish-brown with dark patches.

Tephrosia Candida (Roxb.) DC. - 1, flowering and fruiting branch; 2, flowerbud just before opening; 3, flower, back view; 4, pod; 5, opened top part of fruit showing seeds.

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Growth and development T. Candida is deeprooting. It is slow to establish, but grows steadily thereafter. It forms root nodules with Bradyrhizobium and fixes large amounts of atmospheric nitrogen. In Malesia, flowering occurs year-round; in Vietnam, flowering takes place from August to early September and pods can be harvested from October until February. Over-mature pods will shatter their seed. Maximum growth normally takes place in the second year after planting, but with regular pruning a dense cover can be maintained for many years. Ecology T. Candida grows in the seasonally dry tropics with an annual rainfall of 700 mm to over 2500 mm and a dry season ofup to 4 months. It is cultivated in northern Vietnam, growing well under a rainy season of only 4 months and some showers during the rest ofthe year. It occurs from 0-1600 m altitude with an annual mean temperature of 18-27.5°C, and does not tolerate frost. T. Candida is grown on sandy soils in coastal areas and on very poor, eroded upland soils and mine spoils where few other crops can grow. It tolerates a pH range of 3.5-7; the more acidic soils seem to be more suitable. Waterlogging is not tolerated. The habitat of T. Candida is primary and secondary forest, higher locations in sago palm swamps and disturbed places such as roadsides, river banks, steep slopes and fields. Propagation and planting Prior to sowing, seed is soaked in water for 4-5 hours. It is sown just before or during the rainy season. The germination rate of fresh seed is 95-100%, but decreases rapidly unless stored in a cool dry place. The optimum time for sowing in Vietnam is March-May. When broadcasting, a plant density of 50 000-60 000 per ha is aimed at, requiring 15-20 kg seed. Spacings of 40-90 cm x 10 cm are reported for intercropping, depending on the associated crop. Young plantings should be kept free from weeds. Husbandry In Papua New Guinea, it takes about 4 months for T. Candida to cover the soil, but once established it forms a dense cover keeping the soil weed-free. It responds well to regular pruning. In Vietnam, three cuts for green manure can be made in the first year after planting and 2-3 cuts in subsequent years. In India, 3-4 cuts are made annually during 4-5 years. Cutting should be done 20 cm above the ground. When grown for ground cover, T. Candida should be pruned lightly and frequently. T. Candida has been tried as an alley crop with cassava planted in 7 m wide interrows. Preliminary results indicate a

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greatly increased yield of cassava and a considerable reduction of erosion. On poor soils T. Candida responds well to fertilizers, especially phosphate. Fertilizer recommendations in Vietnam are: P 2 0 5 120 kg/ha, K 2 0 12 kg/ha, CaO 400-600 kg/ha. As no suckers are formed, it is easy to remove when land is to be cleared, but older plants with thick woody stems may be more difficult and costly to uproot. Diseases and pests T. Candida is susceptible to the root fungi Ganoderma spp. and Rosellinia spp. and to the nematode Heterodera radicola. Therefore, care should be taken when growing it in rotation or association with susceptible crops. When weakened by shade and woody with age, T. Candida becomes liable to attack by Fomes spp. It should therefore be replanted at regular intervals. In Indonesia, the Tephrosia beetle (Araeocerus fasciculatus) attacks young pods. It used to be a serious pest making seed of T. Candida difficult to obtain, but it can now be controlled easily with insecticides. Yield Seed yields vary between 350-500 kg/ha. T. Candida can yield well on acid soils where Leucaena leucocephala (Lamk) de Wit does not grow at all. On such soils in Vietnam it realizes an annual green matter production of 10-18 t/ha, increasing the organic matter content of the soil from 1.7% to 4% in 2 years. On fertile soils, 25-30 t/ha of green matter can be harvested annually in 3 cuttings. Genetic resources and breeding A small collection of Tephrosia germplasm is maintained at the Centro Internacional de Agriculture Tropical (CIAT) in Cali, Colombia and at the Southern Regional Plant Introduction Station of the United States Department of Agriculture, Griffin, Georgia. There is no known breeding programme with T. Candida. Prospects The ability of T. Candida to grow well on poor, acid soils makes it an excellent temporary shade and green manure crop and a valuable alternative for Leucaena leucocephala on such soils. It has been little studied in research programmes and deserves further attention. Literature 111 Bosman, M.T.M. & de Haas, A.J.P., 1983. A revision of the genus Tephrosia (Leguminosae-Papilionoideae) in Malesia. Blumea 28: 421-487. I2l Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 230-232. 131 Gichuru, M.P., 1991. Residual effects of natural bush, Cajanus cajan and Tephrosia Candida on the productivity of an acid soil in southern Nigeria.

Plant and Soil 134: 31-36. 141 Le Van Lanh, 1994. Establishment of ecological models for rehabilitation of degraded barren midland land in northern Vietnam. Journal of Tropical Forest Science 7: 143-156. 151 Nguyen, T.S. & Thai, P., 1993. Tephrosia Candida - a soil ameliorator plant in Vietnam. Contour 5: 27-28. L.P.A. Oyen

T e p h r o s i a p u r p u r e a (L.) P e r s . Syn. pi. 2: 329 (1807). LEGUMINOSAE - PAPILIONOIDEAE

2« = 24 Synonyms Cracca purpurea L. (1753), Tephrosia diffusa (Roxb.) Wight &Arnott (1834), T. wallichii Grah. ex Fawc. &Rendle (1917). Vernacular n a m e s Purple tephrosia, wild indigo (En). Fish poison (Am). Indigo sauvage (Fr). Indonesia: pohon nila hutan (Java). Philippines: balatong-pula, balba-latong, tina-tinaan (Tagalog). Cambodia: trôm' khmaôch. Laos: s'a:z kh'a:m moyz (Louang Prabang). Thailand: khram-pa (northern). Vietnam: c[aa]y c[oos]t kh[is] t[is]a, ve c[as]i, do[ax]n ki[ees]m d[or]. Origin and geographic distribution T. purpurea is native to tropical Asia, and is found from India and Sri Lanka to southern China, and through South-East Asia to tropical Australia and the Polynesian Islands. It is now naturalized and cultivated pantropically. Uses T. purpurea is used as green manure for vegetables, rice, coconut and banana, especially in India and Sri Lanka, and on a more limited scale in Indonesia, Malaysia and southern China. It is also applied as temporary shade. When grown as a green manure on saline-sodic soils in Rajastan (India), it is most successful in reducing soil salinity and lowering the pH. In northern India, dry plants are collected for fuel. In Indo-China the seeds are used as a substitute for coffee. The leaves are occasionally used to dye orange-brown, or, in a mixture with Mucuna cyanosperma Schumann, black. Medicinally, all parts of the plant have tonic and laxative properties. The dried plant is deobstruent, diuretic and useful in treating bronchitis, bilious febrile attacks and obstructions of the liver, spleen and kidneys. It is also recommended as a blood purifier, in the treatment of boils and pimples and is considered a cordial treatment. In southern India, a decoction of the fruit is given against intestinal worms and a fruit extract is

TEPHROSIA

used to relieve bodily pains and inflammatory problems. The roots are bitter and a decoction is used as a nematicide for treatment against Toxocara canis larvae which cause a lung disease in Sri Lanka; it is also used against dyspepsia, colic, and chronic diarrhoea and as anthelminthic. Pounded leaves are used to stupefy and catch fish. Information on the fodder value of T. purpurea is conflicting. In India and in South Africa, it is used as a fodder before flowering, but in Australia it is reported to cause livestock poisoning. Properties Green manure of T. purpurea grown in Rajastan (India) contains per 100 g dry matter: C 36 g, N 1.9 g, P 0.3 g, K 1.8 g, Ca 1.8 g, Mg 0.8 g, S 0.4 g. The energy value of the wood of T. purpurea is 14 500 kJ/kg. The toxic properties of T. purpurea are due to the presence of flavonoids; those recorded include rotenone and several ofits isomers named deguelins. One of the deguelins, tephrosin, is poisonous to fish, but not to mammals. The leaves contain up to 2.5% rutin (a flavonol glucoside). The poisonous compounds occur in too low concentrations in the plant to be extracted commercially. Botany An erect or spreading annual or shortlived perennial herb, sometimes bushy, 40-80 cm tall, rarely up to 1.5 m; indumentum sericeous, strigose or velutinous; stem slender, erect or decumbent at base. Leaves imparipinnate; stipules narrowly triangular, 1.5-9 mm x 0.1-1.5 mm; rachis up to 14.5 cm long, including the petiole of up to 1 cm; petiolule 1-3 mm long; leaflets 5-25, obovate to narrowly elliptical, terminal leaflet 7-28 mm x 2-11 mm, lateral leaflets 5-30 mm x 2-11 mm, acute at base, apex rounded to emarginate, venation usually distinct on both surfaces. Inflorescence an axillary or leaf-opposed pseudoraceme, (1.5-)10-15(-25) cm long, sometimes with basal leaf-like bracts; flowers in fascicles of 4-6; bracts to fascicles and to flowers small, bracteoles usually absent; pedicel 2-6 mm long; flower 4-8.5 mm long, purplish to white; calyx campanulate, persistent, cup 1.4-2.3 mm x 1.5-3.2 mm, unequally 4-toothed, teeth pubescent inside; standard broadly ovate, 3.5-7.3 mm x 5-10 mm, clawed; wings 2.5-6 mm x 1.5-3.8mm, auricled on vexillary side, clawed; keel 2.2-4.5 mm x 2-3 mm, auricled on vexillary side, clawed; stamens 10, staminal tube 4-6 mm long, filaments alternately longer and shorter, free part up to 3.5 mm long, vexillary filament free at base, connate halfway, 5-8 mm long; style up to 4.5 mm long, upper half glabrous, stigma penicillate at base. Pod flat, linear, 2-4.5 cm x 3-5 mm, somewhat up-curved to-

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Tephrosia purpurea (L.) Pers. - 1, flowering and fruiting branch; 2, flower, side view; 3, flower, front view; 4, seeds. wards the end, convex around the seeds, flattened between, margins thickened, dehiscent with twisted valves, 2-8(-10)-seeded. Seed rectangular to transversely ellipsoid, 2.5-5 mm x 1.8-3 mm, light to dark brown to black, sometimes mottled. T. purpurea is associated with the vesicular-arbuscular mycorrhizal fungi Glomus heterosporum and Sclerocystis microcarpus in waste sites of coal mines and calcite mine spoils, and is nodulated by Rhizobium. It flowers throughout the year in Java. T. purpurea is a very variable species and many subclassifications exist. Most characteristic is the shape of its pod: convex around the seeds with a distinctive flat area in between. The name T. purpurea is often erroneously applied to the cultivated T. noctiflora Bojer ex Baker which has longer inflorescences, a very long carinal calyx tooth and reticulately ridged seeds. For South-East Asia T. purpurea is subclassified as follows; - subsp. barbigera Bosman & de Haas: vexillary

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filament and staminal tube velutinous; occurring in the Philippines, New Guinea and Australia. Based on flower and inflorescence lengths, further subdivided into 2 varieties: var. barbigera (flower 7-8 mm long, longest inflorescence 11-19.5 cm long) and var. rufescens Benth. (flower 5-6 mm long, longest inflorescence 4.5-11 cm long). - subsp. purpurea: characteristics and distribution as described for the species; vexillary filament and staminal tube glabrous. Ecology T. purpurea occurs naturally in grassy fields, waste places and thickets, on ridges, and along roadsides, in Java up to 400 m altitude. It generally grows at low altitudes, but may be found to 1300 m altitude. In Hawaii, it grows near the seashore. It prefers dry, gravelly or rocky and sandy soils, but in Madras (India) it grows well on loamy soils. It is tolerant of saline-sodic soil conditions.

Transactions of the Indian Society of Desert Technology and University Centre of Desert Studies 10: 39-44. I5l Kiuchi, F.Y., Chen, X., Tsuda, Y., Kondo, K. & Kamar, V., 1989. Studies on crude drugs effective on visceral larva migrans. 11. Identification of nematicidal principles in Tephrosia purpurea Pers. Shyoyakugaku Zasshi 43:(1): 42-49. 161Pandey, Y.N., 1975. A study on an important drug plant Tephrosia purpurea Pers. Quarterly Journal of Crude Drug Research 13: 65-68. I7l Raina, S.N., Srivastav, P.K. & Rama Rao, S., 1986. Nuclear DNA variation in Tephrosia. Genetica 69: 27-33. N.O. Aguilar

Agronomy T. purpurea can easily be propagated by seed. Its growth is often not very luxuriant, limiting its value as a temporary shade crop or green manure. When added to the soil as green manure it increases humus content and induces the formation of large, stable soil aggregates. It produces ample seed and builds up a large seedbank in the soil. Genetic resources and breeding A small germplasm collection is maintained at the Southern Regional Plant Introduction Station, Griffin, Georgia, the United States. There is no breeding programme. Prospects T. purpurea is not generally recommended as a green manure and temporary shade crop, but may nevertheless be useful on salinesodic soils. It deserves further testing for medicinal uses. Literature 111 Bhatnagar, R., 1986. Chemical analysis of Tephrosia purpurea. Transactions of the Indian Society of Desert Technology and University Centre of Desert Studies 11: 99-100. I2l Bosman, H.T.M. & de Haas, A.J.P., 1983. A revision ofthe genus Tephrosia (Leguminosae - Papilionoideae) in Malesia. Blumea 28: 421-487. I3l Botton, H., 1957. Les plantes de couverture. Guide pratique de reconnaissance et d'utilisation des Légumineuses en Côte d'Ivoire [Cover crops. A practical guide for the identification and utilization of legumes in Ivory coast]. Journal d'Agriculture Tropicale et de Botanique Appliquée 4(12): 610-613. 141 Gupta, P.K. & Karan, F., 1985. Prospects of utilizing the common wild herbs and shrubs for the reclamation of saline-sodic soils.

2rc = 22 S y n o n y m s Cracca vogelii (J.D. Hooker) O. Kuntze(1891). Vernacular n a m e s Vogel's tephrosia, fish-poison bean (En). Papua New Guinea: pilawa. Laos: hu: kata:yx (Vientiane). Origin and geographic distribution T. vogelii is native to tropical Africa. It was introduced to tropical America and South and South-East Asia as a cover crop. It was introduced into Java in 1908 and is now found throughout Malesia. U s e s In Indonesia T. vogelii is cultivated as a green manure, wind-break, and temporary shade crop in cocoa, coffee, tea, rubber and cinchona plantations. In Central Africa, the Philippines and Peninsular Malaysia it is used as green manure e.g. in coconut plantations. T. vogelii grows taller than T. Candida (Roxb.) DC. and is thus a good wind-break and shade plant. Because of its dense growth, it is a suitable hedge plant, while its variously coloured flowers make it also suitable as ornamental. In Africa and elsewhere it is cultivated for fish and arrow poison. The poison stupefies the fish, which is then easily caught. Dry crushed leaves are used as an insecticide against lice, fleas, and ticks, and as molluscicide. Medicinally, T. vogelii is used as an abortifacient, as a cure for skin diseases, schistomiasis, as a bactericide, emetic, and purgative, while a weak infusion of the leaves is taken as an anthelmintic. It is not used as a fodder because ofits toxicity. Properties Grown as a green manure in Indonesia, the nitrogen content per 100 g dry matter is 3.7 g for 2-3 months old plants, falling to 1.2 g

Tephrosia vogelii J.D. Hooker Niger fl.: 296 (1849). LEGUMINOSAE - PAPILIONOIDEAE

TEPHROSIA

for 10 months old material, while the phosphorus content drops from 0.8 g to 0.2 g. The leaves of T. vogelii contain the toxins rotenon and several of its isomers: deguelin, tephrosin, iso-tephrosin and hydroxydeguelin-C. Per 100 g dry matter the leaves contain 0.7-4.3 g rotenoids; the stems, roots and seed also contain rotenoids, but in smaller quantities. As deguelin is closely related to rotenon, T. vogelii can be used like Derris spp. as fish poison. The weight of 1000 seeds is 31-37 gDescription A softly woody, branching herb or small tree with dense foliage, 0.5-4 m tall, with velutinous to sericeous indumentum. Stem and branches tomentose with long and short white or rusty-brown hairs. Leaves arranged spirally, imparipinnate; stipules 10-22 mm x 3-3.5 mm, early caducous; rachis 5-25 cm long, including petiole of up to 3 cm, pulvinate; petiolule 1.5-5 mm long; leaflets in 5-14 pairs, narrowly elliptical to elliptical-oblanceolate, up to 7 cm x 2 cm, base acute to obtuse, apex rounded to emarginate, venation most distinct on lower surface, silky tomentose.

Tephrosia vogelii J.D. Hooker - 1, flowering branch; 2, flow'erbud just before opening; 3, flower, back view; 4, pod; 5, part of opened fruit showing seeds.

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Inflorescence a terminal or axillary pseudoraceme, 8-26 cm long, rusty tomentose; basal bracts leaf-like; peduncle stout, as long as pseudoraceme; flowers in fascicles of 2; bracts to fascicles orbicular to obovate, cuspidate, about 1.5 cm long, bracts to flowers narrowly elliptical to spatulate, about 1 cm long; flower 18-26 mm long, fragrant when fresh, white, violet, purple or blue; pedicel up to 23 mm long; bracteoles sometimes present on calyx; calyx campanulate, tube 4-6 mm x 6.5-10 mm, pale greenish brown, outside sometimes sericeous, usually 4-toothed, teeth puberulous to sericeous within, vexillary tooth broadly ovate, 5-12 mm x 8-12 mm, lateral teeth oblong, 4.5-10 mm long, apex rounded, the carinal one narrow, boat-shaped, 6-15 mm long, acute; standard suborbicular, 20-28 mm x 24-32 mm, auricled at base, apex emarginate, the apical half and the margins puberulous to sericeous within, claw 3-5.5 mm long; wings 17-22 mm x 11-13 mm, auricled, inside sericeous, clawed; keel 15-20 mm x 10-12 mm, slightly auricled, clawed, hairy only on carinal side; stamens 10, staminal tube 19-20 mm long, glabrous, vexillary filament free at base and connate halfway, 22-26 mm long, glabrous, free parts of the other stamens alternately longer (6-11 mm) and shorter (4-7 mm); style bent through 70°, 11-15 mm long, bearded on both sides, stigma glabrous. Pod linear, slightly turgid, 5.5-14 cm x 0.8-1.8 cm, brown or green, woolly to sericeous, 6-18-seeded. Seed ellipsoid to reniform, 5-7 mm x 3-5 mm, dark brown to black. Seedling with epigeal germination; cotyledons rather thin, leaf-like, green, long persistent; first leaf simple, second leaf usually 3-foliolate. Growth and development Under favourable conditions, T. vogelii grows rather fast, usually exceeding the growth rate of other green manure legumes, such as Crotalaria micans Link, C. trichotoma Bojer and Mimosa diplotricha C. Wright ex Sauvalle. In Java, initial growth is slow, plants attaining only 8 cm at 6 weeks after planting. Subsequent growth, however, is rapid and plants may reach 36 cm at 3.5 months and 2 m or more at 1 year after planting. In Java, flowering and fruiting starts 10-12 months after planting and T. vogelii does not live much longer than one year. In Sri Lanka, however, it may grow for at least two years, and under favourable conditions even longer. T. vogelii is tolerant to repeated pruning only under favourable conditions; drought often stops resprouting. Other botanical information T. vogelii is closely related to T. nana Kotschy ex Schweinf.

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The latter is a native of Africa but is cultivated and naturalized in Java and can be distinguished by its 3-4 flowers per fascicle, smaller flowers and large number of seeds in relatively short pods. T. vogelii also greatly resembles T. Candida, but is easily distinguished by its generally more luxuriant foliage and larger, more hairy pods. It yields a larger amount of green material when young than T. Candida, but its life cycle is shorter. African specimens of T. vogelii usually have smaller calyx teeth. In East Africa, a white-flowered form predominates, in West Africa a purple-flowered form. Ecology T. vogelii is found in widely varying habitats, including savanna-like vegetation, grassland, forest margins and shrubland, waste land and fallow fields. It is tolerant to drought, strong wind and grazing. Burning has little effect on T. vogelii, as it resprouts readily due to its deep root system. It occurs in climates with an annual rainfall of850-2650 mm and an annual mean temperature of 12.5-26.2°C and is found up to 2100 m altitude. It grows well on andosols not subject to flooding and on well drained loams with pH 5.0-6.5 and is also tolerant to poor soils with low pH. In acid soil, it grows much better than Leucaena leucocephala (Lamk) de Wit and forms root nodules and fixes atmospheric nitrogen where the latter does not. On poor soils, however, growth of T. vogelii is slow and more prone to diseases. Propagation and planting T. vogelii is commonly propagated by seed. Air-dried seed can be stored in sealed containers for at least 1.5 year. Fresh seed should preferably be stored for 2 months before planting. Without treatment, the germination percentage is 65% and the seedling survival rate about 60%. Soaking in warm water (45°C) for 5 minutes stimulates germination. For a green manure crop, the recommended spacing is 40 cm x 40 cm, with 2-3 seeds per hole, when planted in hedges the spacing should be 1.5 m between the rows. For large plantings, sufficient seedlings should be available for replanting in case of a low survival rate. When sown in rows, the recommended sowing rate is 5kg/ha and when broadcast 8-13 kg/ha. Planting should be done at the beginning or in the middle ofthe rainy season. Husbandry Maximum biomass yield of green manure is obtained before flowering starts. To obtain tangible results, the plant material should be dug in towards the end ofrainy season immediately after it has been cut. If the plants are weakly branched, they should be lopped to promote branching. Results of experiments in Indonesia have indicated that soils into which a 3-month-old

T. vogelii crop had been incorporated showed an increase in organic matter (from 8% to 10%), nitrogen (from 0.4% to nearly 0.5%), phosphorus and potassium. The increase is larger when 2month-old material is incorporated. In Indonesia and Sri Lanka, a 5-month-old crop was found to yield about 27 t/ha of green material. About 40% of the material was provided by the leaves and twigs alone, and the remainder by the stalks and roots. In Central Java T. vogelii may yield 4.4-4.8 t/ha green material about 110 days after planting. The use of T. vogelii green manure was found to increase yields of subsequent maize or rice crops by about 0.5 t/ha per planting season. Diseases and pests In Java, stems of T. vogelii are liable to serious attacks by Corticium salmonicolor, especially after lopping. When tested in the United States as a pesticide-producing crop, rootknot nematodes caused very serious damage. In Central Java, Helopeltis spp., a serious pest of cocoa, can also heavily attack T. vogelii. Because of this, T. vogelii is no longer recommended for planting in Java. Handling after harvest To make fish poison, leaves and small branches are gathered as needed; the leaves are macerated in water or beaten to a pulp and then thrown into the water. After about 10 minutes, stupefied fish float to the surface and can be easily collected. Pounded roots are used similarly. Genetic resources and breeding No germplasm collections of T. vogelii and its relatives are known to be maintained and no breeding programme is known to exist. Prospects The prospects of T. vogelii as a green manure, temporary shade or wind-break are not promising compared to T. Candida, Crotalaria spp., or Leucaena leucocephala. However, T. vogelii may be useful if suitable alternatives are absent. Efforts should be made to select strains that are promising for use as green manure or to restore soils. Literature 111 Bosman, M.T.M. & de Haas, A.J.P., 1983. A revision of the genus Tephrosia (Leguminosae-Papilionoideae) in Malesia. Blumea 28: 421-487. I2l Chiu, S.F., 1989. Recent advances in research on botanical insecticides in China. American Chemical Society Symposium Series 387: 69-77. 131 Duke, J.A., 1981. Handbook of legumes of world economic importance. Plenum Press, New York, United States, pp. 232-233. 141 Minton, N.A. &Adamson, W.C., 1979.Response of Tephrosia vogelii to four species of root-knot nematodes. Plant Disease Reporter 63: 514. 151

THESPESIA

Niyungeko, M.R., Ngurale, A., Ngoic, M. & Sanginga, N., 1990. Early nodulation and growth of Tephrosia and Leucaena on an oxisol at Yangambi, north-eastern Zaire. Nitrogen Fixing Tree Research Report 8: 85-87. 161 Wargadipura, R., 1973. Macam-macam tanaman pupuk hijau untuk merehabilitasi tanah perkebunan teh [The use of some green manures for soil rehabilitation in tea plantations]. Menara Perkebunan 41(1):7-11. B. Sunarno

T h e s p e s i a p o p u l n e a (L.) S o l a n d . e x Correa Ann. Mus. Hist. Nat. Paris 9: 290 (1807). MALVACEAE

2n =24, 26, 28 Synonyms Hibiscus populneus L. (1753), Thespesia macrophylla Blume (1825), Hibiscus populneoides Roxb. (1832). Vernacular n a m e s Pacific rosewood, portia tree (En). Cork tree, seaside mahoe, milo (Hawaii) (Am). Indonesia: baru laut (Indonesian), waru laut (Javanese), salimuli (Moluccas). Malaysia: baru-baru (general), baru laut, bebaru (Sarawak). Philippines: banalo (Tagalog), tuba-tuba (Bikol), balu (Sulu). Cambodia: baëhs sâmut(r), chréi sâmut(r). Thailand: pho-thale (central). Origin and geographic distribution T. populnea probably originates from the Asi